Xcode project: created "QuakeSpasmSDL2" target. It expects a copy of SDL2.framework to be in /Library/Frameworks

changes from "QuakeSpasm" target:
- remove double quotes around LIBRARY_SEARCH_PATHS values, this breaks linking on my OS X 10.6/Xcode 3.2.6 system
- drop ppc support
- add USE_SDL2 define
- bump minimum sdk deployment target to 10.5 as required by SDL2

Tested on OS X 10.6.8/Xcode 3.2.6, and OSX 10.9.4/Xcode 5.1.1.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1055 af15c1b1-3010-417e-b628-4374ebc0bcbd
Correct the buttonremap table for SDL2 so K_MOUSE4/K_MOUSE5 work.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1056 af15c1b1-3010-417e-b628-4374ebc0bcbd
revert exec'ing default.cfg and config.cfg upon in-game gamedir changes.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1057 af15c1b1-3010-417e-b628-4374ebc0bcbd
allow KP_ENTER to function as K_ENTER in menus, console, etc., after r1042.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1058 af15c1b1-3010-417e-b628-4374ebc0bcbd
copyright years, general tidy-up, remove unused d_ifacea.h.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1059 af15c1b1-3010-417e-b628-4374ebc0bcbd
rediff the extra quake_retexturing_project.patch so it applies cleanly.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1060 af15c1b1-3010-417e-b628-4374ebc0bcbd
rediff the extra fs_search_order.patch so it applies cleanly.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1061 af15c1b1-3010-417e-b628-4374ebc0bcbd
Add note about limitations of the 'game' command to the readme files

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1062 af15c1b1-3010-417e-b628-4374ebc0bcbd
in_sdl.c: rewrite TEXTINPUT handling a bit.


git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1063 af15c1b1-3010-417e-b628-4374ebc0bcbd
Rename some functions for consistency.


git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1064 af15c1b1-3010-417e-b628-4374ebc0bcbd
slightly revise the game command known bug infos.

git-svn-id: svn+ssh://svn.code.sf.net/p/quakespasm/code/trunk@1065 af15c1b1-3010-417e-b628-4374ebc0bcbd