Bugfixes and improvements on cmake installation.

The installation used to add the HDF5 dependencies to the STATISMO_INCLUDE_DIRS.  This can cause troubles when other HDF5 libraries (e.g. the ones from ITK are used). The path to these libraries is now given in the STATISMO_HDF5_XXX variables.
Merge remote-tracking branch 'origin/master'

Conflicts:
	CMakeLists.txt