add generic action
Addes a two new url that generate a "user report"

This commit add two new urls that allows superuser to export a list of
all the current users. This url generates a csv for now.
Merge pull request #695 from opengeo/iss-644-csv-export-clean

Iss 644 csv export
add activity report, minor rearrange from ba11c86
Merge branch 'master' into integration

Conflicts:
	admin.py
	urls.py