Chile local flavor: New form select field: CLCommuneSelect

Included a list of commune as choices in localflavor/cl/cl_communes
Included a select field in localflavor/cl/forms.py

Also included a dict with the name of the communes mapping to the region
they belong to in localflavor/cl/cl_regions, in case someone wants to
validate the correspondence of the commune in the region.

Finnaly, changed the localflavor/cl/forms.py file to fit every line in
80 characters
Included a new test for the CLCommuneSelect widget.

It tests the generated html with the list of commune choices in the localflavor.cl.cl_communes file