Pick cleanup: Don't display messages with word counts

This gets rid of the messages shown below the roleup and above the
translate actions. That data is meant to be shown in the roleup.
Pick cleanup: Don't display the legacy summary in the roleup

These changes are meant to get us closer to Evernote, and reduce conflicts.
Refactor retrieving the common overview context

Pick notes: Had to do heavy adjustments since we serve part of the data using
    JavaScript, and our overview view is very different than Evernote's.

Conflicts:
	pootle/apps/pootle_translationproject/views.py
	pootle/core/helpers.py
Dirty fix to get the TP overview working

The following exception was being thrown: 'TranslationProject' object has
no attribute 'is_dir'.

Not sure why the `request.ctx_obj` (I even tried `request.resource_obj`) in
`get_overview_context` is not working, because it should.
Partial pick: We won't always have a resource path

Pick notes: This is picking the rest of the commit that we didn't have.
Cleanup: removed dead code