Merge branch 'master' into devel_better_data_management

# Conflicts:
#	VERSION
#	earthdiagnostics/constants.py
#	earthdiagnostics/datamanager.py
#	earthdiagnostics/diagnostic.py
#	earthdiagnostics/earthdiags.py
#	earthdiagnostics/ocean/heatcontent.py
#	earthdiagnostics/ocean/interpolate.py
#	earthdiagnostics/ocean/regionmean.py
#	earthdiagnostics/ocean/siasiesiv.py