codeblocks: Remove unused files, minor tuning.


git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk/quakespasm@1106 af15c1b1-3010-417e-b628-4374ebc0bcbd
Xcode: rename QuakeSpasmSDL2 target to QuakeSpasm-SDL2

git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk/quakespasm@1107 af15c1b1-3010-417e-b628-4374ebc0bcbd