Initial Blackberry10 support

Some things still need to be set before calling cmake, namely:
export QTDIR=/path/to/BB10/qt
export PATH=$QTDIR/bin:$PATH

The cmake call line looks like this:
cmake -DCMAKE_TOOLCHAIN_FILE=../Toolchain-blackberry-armv7le.cmake -DCMAKE_BUILD_TYPE=Debug -DCMAKE_INSTALL_PREFIX=$PWD/install -DQt5Gui_EGL_LIBRARY=$QNX_TARGET/armle-v7/usr/lib/libEGL.so -DQt5Gui_GLESv2_LIBRARY=$QNX_TARGET/armle-v7/usr/lib/libGLESv2.so ..

I wonder if we can auto deteted the libs explicited above.