provide a simple oembed API

This will simply set the format to 'overlay' for all
incoming URLs.
add merge instance script
add support for locale teritory in need_js_i18n
fixup "make all badge select forms look alike"

readd the "no badge" option for radio buttons
Revert "allow anyone with badge.index to see global badges"

This reverts commit 3c5b616ca0809144345895b2788a8e117a008cae.
badge redirect 1: set came_from for badge type index
badge redirect 2: pass came_from to form request
badge redirect 3: pass came_from to form
badge_redirect 4: pass came_from to post request
badge redirect 5: redirect to came_from
Merge pull request #831 from xi/feature-fix-badge-manage-redirects

fix badge manage redirects
better error message for deleted accounts
Allow instance moderators to assign global proposal badges
Fix message to opponents help text
Merge pull request #832 from veryrandomname/hotfix-velruse-better-error-deleted-users

Velruse: better error message for deleted accounts
i18n: extract and update all
translatable strings
rename event/all title
i18n
pep8