Ring Racers CMake + Debug build improvements

General CMake improvements:

• Added configure presets:
  • "default": Build a Release build using the Ninja generator, with Debug symbols exported to their own file.
  • "debug": Build a Debug build using the Ninja generator.
• Added some git aliases for running CMake quickly.
• EXE naming improvements:
  • If SRB2_SDL2_EXE_NAME is left blank, it now uses a default name by appending the branch name as a suffix. (For instance, building this branch on Windows will call the EXE srb2win_cmake-rr-ports.exe.) No branch suffix is added for the master branch.
  • Added SRB2_SDL2_EXE_SUFFIX, which adds an extra suffix to the end of the EXE name.
• Sources are back in CMakeLists.txt. (The sourcefile method was not able to update the CMake cache.)
• Always build GME, regardless of system library option.
  • GME compiles with a really slow YM2612 emulator on Linux by default, so always compiling means we can enforce something faster.
• Disable dynamic base on Windows.
  • Fixes crash reports on Windows CMake builds.
• Split the dependency scripts into their own files.
• Exported additional version information to the game:
  • What kind of build type the compile is.
  • Whenever or not the compile has uncommitted changes.
  • Whenever or not the compile has optimizations enabled.
  • Branch is now able to determine detached HEAD.
  • Commit hash is separated from commit summary.
  • Most of this stuff is unused right now. Ring Racers uses all of this stuff for debug build title screen, but I decided against porting this part currently as this branch is already chunky enough.

Debugging improvements:

• Added -nofork command line parameter to disable SDL forked signal handler.
  • This allows for GDB to consistently attach to the correct process.
• Added assert console command.
  • This prints whenever or not this build has assertions enabled.
• Fixed PARANOIA builds.
  • Removed a few faulty asserts that made these builds unusable.
  • Fixed SCRAMBLE_REMOVED doing the mobj scramble in the middle of removing an object instead of at the very end.
  • Replaced the unknown thinker I_Error with an assert.
  • Made PARANOIA's mobj reference checks more useful:
    • The existing warning no longer spams the console every tic.
    • The existing warning now prints mobj address, mobj type, and reference count.
    • P_SetTarget, when it causes a reference to go negative, now prints mobj address, mobj type, thinker function, reference count, and source code line number.
  • Compiling Debug builds now always enables everything that SRB2_CONFIG_DEBUGMODE also enables. (PARANOIA, RANGECHECK, ZDEBUG, and PACKETDROP)

Additionally, add a deprecation warning when using the Makefile.