Conquest 9.0 Stable release

This is a long overdue release of Conquest.

The musicpak is optional. To use it, unpack it inside your ~/.conquest/ directory.

There have been many changes (internal and external) in this version
compared to the previous 8.5 version.

The following are the highlights -- look at the commit log for
details.

• Conquest is hosted at GitHub now. The "conq" project at SourceForge
  has been deleted.

  https://github.com/jtrulson/conquest

• Conquest is built with a C++ compiler now. Your compiler must
  support the C++11 standard - this includes g++ 4.9 or better, and
  clang++ 3.4 or better. Conquest is still C, but with some C++
  constructs and containers in use. I would like to move toward
  more C++ use over time.

• The user and system conquestrc configuration files are now named
  conquest.conf. If you have an existing ~/.conquest/conquestrc,
  you should rename it to ~/.conquest/conquest.conf to preserve your
  settings.

• The curses client has been removed. It could no longer compete
  with the GL client, and some things, like an object's (ship,
  planet, etc) size was just impossible to implement properly.

  "conquestgl" (the OpenGL version) has been renamed to "conquest".

• The protocol has changed. A lot of shortcomings in the v6
  protocol have been fixed. Support for the v6 protocol is still
  provided, but only for playing back old .cqr (Conquest recording)
  files made by previous versions of Conquest.

• The internal clocks have been re-implemented, yielding millisecond
  accuracy. Previously, you were limited to 1 second accuracy.

  This has the side effect that bombing planets is much faster now.
  Original Conquest specified that you had a chance to kill up to 3
  armies every second of bombing. With the previous 1 second
  resolution, you could only bomb up to 1 army per second.

  As a result, bombing will seem about 2-3 times faster than
  previous versions. This was the way it was intended in original
  Conquest, and actually helps to move a game along faster.

• The Common Block (CB) which represents the Universe, has been
  reworked. It is now named 'conquest.cb'.

  In the conqinitrc file, there is a "global {}" section that
  specified how many ship slots you could have, how many planets,
  etc.

  Previously, this data was ignored as Conquest hardcoded all of
  that stuff, and the CB was hardcoded to a fixed size.

  Now this data is used to construct a custom CB, and those
  parameters are supplied to the client so that it can construct a
  custom CB matching that of the servers'.

  You can have up to 256 planets, 256 ships, 64K users, 256 message
  slots and 256 history entries.

  Building a universe is a lot more flexible now since the old
  hardcoded methods are gone.

• Planets, suns, and ships have a 'size' value now (expressed in
  CU's).

  Previously these objects were all 300 CU's in size (due to curses
  client limitations).

  Now they can vary. The scanning range, orbital path, and damage
  potential of a planet or sun also now depends on it's size. Be
  careful of Suns now, they have a much larger reach than they used
  to :)

  For ships, cruisers are a little larger than destroyers.
  Destroyers are a little larger than Scouts. Previously it was
  fairly random, depending on the texture used, and in some cases
  (Romulan) a team scout was much larger than the team cruiser.

• The homeplanet, and core flags of a planet are fully implemented
  now. They were present in previous versions, but ignored.

  "core" planets are used to mark a planet that must be taken in
  order to conquer the universe.

  "homeplanet" planets, are team owned planets that are defendable
  by team robots.

  Previously, which planets were core, and which were homeplanets
  were hardcoded into the game. Although you could change some of
  the characteristics of the planets, you were still required to
  conquer a hardcoded 25 planets in order to take the universe. In
  addition, each team had 3 hardcoded home planets defendable by
  robots.

  Now, you can mix/mash these up as you desire. The only
  requirement is that each team has at least one homeplanet. You
  can even specify that only one planet is needed to take the
  universe if you like. These changes make it possible to more
  fully customize a universe of your choice.

• Some new server flags have been added:

  • NoTeamWar - when set, ships are prohibited from declaring war
    with their own team.

  • NoDrift - when set, the Drift bug is disabled.

  • Closed - When set, the game is closed/private, and only players
    with an account on the server, and the PLAYWHENCLOSED user flag
    set, will be able to login and play.

• UDP has been reimplemented, much more robustly this time. UDP
  packets are tagged with a sequence number now so that
  out-of-order, duplicate, and missing packets can be detected and
  handled properly.

  In addition, UDP is now negotiated with the server, via the
  protocol, eliminating the hacky way we were doing it before.

• The old tactical grids have been removed and replaced with a new
  circular grid. The old tac grids only worked in LR scan, and were
  not scalable, so they were kind of useless, even though they might
  have looked nice.

  The new circular grid is much simpler and simply draws 10
  concentric circles around your ship, spaced at 1000 CU intervals.
  It's available in both LR and SR scans, and is always scaled
  properly according to your SR/LR scan selection and your applied
  mag factors.

  It can be enabled via the Options menu, or toggled on and off in the
  game with ^G.

• The ability to make client recordings has been removed. You can
  use a screen recorder (like kazam on linux) to record games if you
  like.

  Server recordings are still supported.

• The TAD (Target Angle/Distance) display, if enabled, is
  automatically updated every second with current data when getting
  information on a ship or planet.

• Using the -G switch to conquestd, now allows a single server
  installation to serve multiple independant games. See
  docs/server-guide.md for details.

• The Universe is now "limited" to +/- 200 million CU's in each
  direction. This is still pretty huge.

• The -m option to conquest (query metaserver) is gone, and is now
  the default when conquest is run without a server argument (-s
  ...).

• The 3 main configuration files used for the planets, textures, and
  sounds (conqinitrc, texturesrc, and soundrc, respectively) are
  always overwritten on a make install or package update. If you
  would like to make changes to these files that survive an update,
  copy them with a '.local' extension. When loading these files,
  Conquest will always load a '.local' variant of the file first, if
  present.

  This is only of interest to people who want to run a server.

• we use the stb_image.h image loader now and all Conquest textures
  have been converted to PNG from TGA.

• Many hundreds of warnings, dozens of bugs and an overhaul of much
  "under the hood" code has been done.

  To see all the gritty details, just go the the GitHub page and
  read the commit history.