add libann dependency
replaced ann cmake patch with a python version
added opengm dependency
ann.cmake: install include files, too
added boost-serialization dependency
boost.cmake: use correct msvc version if more than one version is installed; install serialization libs, too
preliminary pgmlink.cmake
pgmlink.cmake dependency complete
add option to build pgmlink (requires cplex)
Merge branch 'master' into tracking

Conflicts:
	CMakeLists.txt
upgraded zlib from 1.2.7 to 1.2.8
fixed broken hdf5 download url
fixed broken freetype download url