enable plugins to override templates

Currently, templates provided by plugins will searched with
last priority, thus overriding via plugins is currently not
possible.

Change-Id: I05981b75e147d5e1ae952144d4acc8c909513444
Closes-Bug: #1289305
Allow translator to control the word order (update extra spec)

Change-Id: Ia7aeeef0e8cc957a9167cdfe89f12f3c327a52b8
Closes-Bug: #1291513
Mark string in routerrule template translatable

It also removes an unnecessary colon in "Retreive Password" form.

Closes-Bug: #1291522
Change-Id: I7d2d52398ccf5517bf09bbd3f76acdd729fd3f4b
Fix username's maximum length to match the backend

when create a user, we can input length more 255 character,
but it will report a error 'User name should not be greater
than 255 characters (HTTP 400)'.

Change-Id: Ib2a3d2f6783e1c107d9a2cf87877442a9171480d
Closes-bug:#1291216
Merge "Mark string in routerrule template translatable"
Merge "enable plugins to override templates"
Merge "Allow translator to control the word order (update extra spec)"
Merge "Fix username's maximum length to match the backend"