Update set_globattr.py
Deleted the indice_group parameter.
Update set_globattr.py

bekozi's commit:
Added a "datetime" import. Some changes were made to the if
statement that sets the temporal grouping mode. Change the
grabbing of the history attribute to use "getattr" so it could
be more easily overloaded in the OCGIS calculations.
Merge remote-tracking branch 'upstream/test' into test

Conflicts:
	icclim/set_globattr.py