Improve help system

[vinc]

• Add -h and --help to all commands
• Add manual page explaining how to use the system
• Update images in doc
• Update shields in README
• Update HTML pages for the website at http://moros.cc

[vinc]

A test is generating a protection fault when print is called for the second time when we add help to read, and many other commands but not for some like write. Adding some debug output in the code sometime prevent the exception from happening and the test become successful.

DEBUG: EXCEPTION: GENERAL PROTECTION FAULT
DEBUG: Stack Frame: InterruptStackFrame {
    instruction_pointer: VirtAddr(
        0x2bcd5e,
    ),
    code_segment: 24,
    cpu_flags: 0x93,
    stack_pointer: VirtAddr(
        0x100001e82b0,
    ),
    stack_segment: 0,
}

[vinc]

The commit that added help to read also prevented the ACPI shutdown from the halt command, but this issue disappeared a few commits later..

[vinc]

The makefile has a new command make website to generate the HTML pages in www by running www/build.sh for the website at http://moros.cc

[vinc]

The makefile also has a new option monitor for make qemu monitor=true to be able to take a screenshot with:

nc -N 127.0.0.1 7777 <<< "screendump moros.ppm"

The files can then be converted with:

for img in *.ppm; do convert $img ${img%.*}.png; done