remove `shared_url` helper and tests (bug 1024185)
Merge pull request #2198 from cvan/rm-shared-url

remove `shared_url` helper and tests (bug 1024185)
remove dead MAMO/MMMO mobile code (bug 1024136)
Merge pull request #2195 from cvan/lamo-mamo-mmamo

remove dead MAMO/MMMO mobile code (bug 1024136)
remove django-mobility (bug 1019516)
Merge pull request #2196 from cvan/no-mobility

remove django-mobility (bug 1019516)
use a rocket if nothing else there (bug 1016671)