remove references to global header/footer submodules (bug 1025263)
Merge pull request #2218 from cvan/canned-response

remove `type` from `CannedResponse` model (bug 1021837)
Merge pull request #2215 from cvan/rm-global

remove references to global header/footer submodules (bug 1025263)
Moved apps/files/ to mkt/ (bug 1021200)
remove legacy AMO tasks (bug 1026255)