Restructure CVariable files

[pcarruscag]

Proposed Changes

Breakup CVariable classes into individual hpp and cpp files, with inlines defined in hpp.
Revise the includes of client classes (CSolver and derived).

Related Work

Addresses part of #583
Preparation for #716

PR Checklist

• I am submitting my contribution to the develop branch.
• My contribution generates no new compiler warnings (try with the '-Wall -Wextra -Wno-unused-parameter -Wno-empty-body' compiler flags).
• My contribution is commented and consistent with SU2 style.
• I have added a test case that demonstrates my contribution, if necessary.

[pcarruscag]

Is there any reason to link against individual object files instead of the static library?

[talbring]

Actually there is no reason 👍 Thanks!

[economon]

agreed.. I think that's just legacy behavior from before the libSU2Core.a was added around the time of the in-memory python wrapper

[economon]

agreed.. I think that's just legacy behavior from before the libSU2Core.a was added around the time of the in-memory python wrapper

[economon]

Looks like you are already doing it, but this is a nice opportunity to fix any indentation / white space / line ending issues when creating these new files. Can you please double check?

[pcarruscag]

I think indentation was already ok, I striped all trailing white spaces now.
There are also many (many...) comments that were copied and do not match the function, that is not a huge deal since these methods explain themselves. I fixed some but I will not fix all of them...

[economon]

Certainly not expected that you fix them all.. let's get some help on that in a later sweep once merged.

Thanks for the clean up! Can you also verify that all line endings are linux style and not windows format?

[pcarruscag]

Apparently everything was LF-ended already, at least the IDE I use did not pick up anything.

[talbring]

Thanks @pcarruscag! Just went through all the changes and I have nothing to complain. Lets continue with this restructuring ... I think it will really help with the readability and maintenance.

[pcarruscag]

Thanks @talbring. You were right about the includes, even for these classes with lots of inlines everything seems to work fine if only the "client" solver includes the classes it uses.