editing a page no longer redirects to explorer. success messages added to locking/unlocking process.
corrected redirect
mistake
creating should also remain on page after submit
Merge branch 'master' into return-to-edit
updated tests
Merge pull request #697 from davecranwell/return-to-edit

Editing/Publishing/Submitting a page no longer leaves the page editor
Fixed login form to reference USERNAME_FIELD

Was hardcoded to say 'username' when USERNAME_FIELD may be 'email' etc.
Fixed login placeholder for custom User model