Fixed compilation errors on Windows
Fixed compilation error on some compilers
Support Chrome portable native client
Fix crash with empty interaction groups
Fixed error when running in double precision
Updated version number to 6.1
Very minor optimization to DIIS
Disable OpenCL by default on Macs
Fixed anisotropy for terminal residues
Fixed error in OpenCL MonteCarloBarostat in double precision
Lots of cleanup to how documentation gets built