Added links to README
Updated CMakeList to find GSL, HDF5, LAPACK
Improved Doxygen options
Small correction in README and Doxygen
Added logo in README
Merge branch 'master' of https://github.com/wpoely86/CheMPS2

* 'master' of https://github.com/wpoely86/CheMPS2:
  Added logo in README
  Small correction in README and Doxygen
  Improved Doxygen options
  Updated CMakeList to find GSL, HDF5, LAPACK
  Added links to README
Fixed bug in finding the HDF5 libs