try to optimize edit theme form (bug 855619)
Merge pull request #914 from ngokevin/perfedittheme

try to optimize edit theme form (bug 855619)
reflect @cvan's context_processor fix
refactor category save on theme edit, don't spawn reupload task every time
redirect users after accepting TOS from developer API page (bug 860111)
remove 404 links to "Unsubscribe" in Marketplace emails (bug 802379)