- Added Gain control
- Changed default acquisition mode to grayscale
- Fixed a signed/unsigned compare issue
- Implemented frame resizing
- Implemented automatic buffer resizing on frame resize
- Corrected camera initialization so that it attempts to put the camera in Mono8
  but does not fail if this doesn't succeed.

another fix to make OpenCV more friendly for iOS developers. We now use libc++ instead of libstdc++ and clang instead of gcc to build opencv2.framework.

Memory leak in color-blob-detection sample fixed;
Default face size in face-detection is set to 20%;
Error handling improved;
Some possible mat leak fixed;
Manager verison and engine interface version incremented to fix incompatibilities;
Docs updated;