Added ability to cut and copy the current line in UITextInput without selecting
Fixed a crash that happened when attempting to select text with left key + shift
switched to max() to make sure colEnd arg >= 0 (instead of if testing)
Added safe_delete to Lua API which deletes passed object on next frame, added stopTrackingChild to PhysicsScreen, contact events now dispatched after box2d step completes.
Added clampDefault and mipmapsDefault settings to MaterialManager to set the texture clamping and mimap generation defaults
Added getScreenEntityById and getScreenEntitiesByTag helper accessors to ScreenEntity
Added platformer game example to Lua examples
Optimized PolyUITextInput::insertLine
Implemented OSBasics::fileExists

This first checks if the file exists in physfs, and if not, it checks the actual filesystem using OS calls.
Merge pull request #252 from CIB/file

Implemented OSBasics::fileExists
Merge pull request #251 from CIB/cleanup

Optimized PolyUITextInput::insertLine
Merge pull request #248 from TheCosmotect/left-select-fix

Fixed a crash that happened when attempting to select text with left key + shift
Merge pull request #244 from TheCosmotect/copycut

Added ability to cut and copy the current line in UITextInput without selecting
Merge pull request #249 from CIB/documentation

Doxygen stuff
Added a dummy file so that the tags folder gets created automatically
Added .vert and .frag to list of extensions openable by text editor in IDE
Moved physics event dispatching to fire after every Step() call, not after all Step() calls are complete
Fixed material editor changing names in the material browser incorrectly
Rewrote material editor to use IDE property sheets
Prevent editor from getting copy/paste events if deactivated