Fixes crash from r15715 where a VBChunk* was released but not set to NULL

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15721 3db68df2-c116-0410-a063-a993310a9797
Merge 'remotes/trunk'
update the in-game hotkeys page following r15671

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15722 3db68df2-c116-0410-a063-a993310a9797
Some tweaks to profiler2:
* separate the HTTP profiling server from the on-screen profiler
* allow shutting down the HTTP profiler
* print messages when enabling/disabling HTTP and GPU profilers

Patch by kingbasil, fixes #1862

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15723 3db68df2-c116-0410-a063-a993310a9797
Automated build.

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15724 3db68df2-c116-0410-a063-a993310a9797
Sets default compiler for OS X build to clang, using hack that should be replaced if we upgrade premake.
Fixes linking error in ICU build from build-osx-libs.sh (it was setting the C++ compiler to clang, which is the C compiler, so it wouldn't automatically link to the c++ lib). Now build-osx-libs.sh and the game should use clang and whichever c++ lib is the default

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15725 3db68df2-c116-0410-a063-a993310a9797
Fixes clang warning of deprecated finite function in FCollada on OS X 10.9, patch by leper, refs #2097

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15726 3db68df2-c116-0410-a063-a993310a9797
fix heal_barracks tech

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15727 3db68df2-c116-0410-a063-a993310a9797
Petra: some tunings in tech research following the merge of balance branch

git-svn-id: http://svn.wildfiregames.com/public/ps/trunk@15728 3db68df2-c116-0410-a063-a993310a9797
Merge 'remotes/trunk'
Temporary changes to ease testing SDL2 on Windows
Fix for game crashing at shutdown with SDL2 on Windows
Allows using SDL2 hardware color cursors instead of our own platform specific implementations
Adds EXPERIMENTAL untested SDL2 multidisplay support
First attempt at handling SDL2 text input events in place of the old keyboard events that provided a Unicode character (this was long deprecated and later removed in RC, causing our SDL2 build to fail)
Missed change from last commit
Some cleanup.
Adds experimental --sdl2 option for premake to choose SDL 2 build.
Fixes warning about unused function in cursor code.

Conflicts:
	build/premake/premake4.lua
Fixes breakage due to texture API change
Adds precompiled SDL2 win32 binaries
Fixes errors restarting the engine with SDL2 (the window must be destroyed at shutdown), based on patch by yashi