Account/register: Show login field when registering via Omniauth

There's no reason to prevent a user from changing their login, it
might actually be required if the login has already been taken.
Fix flash message shown when an account is inactive

Show different messages depending on whether the user is locked or
registered. In the latter case, also show different messages depending
on the self_registration setting (manual activation vs. mail).
Fixed a host of irritations regarding maintaining filters after bulk updates.
Removed commented out call.
Add cukes
Prevent page reload on time period selection
Merge branch 'fix/show_login_field_on_omniauth_register' into dev
Use SVG Travis badge

PNG looked ugly on high-resolution displays.
Moved show warning method to timelines controller.

I don't actually think this was exactly related to the error in bug 7186 - i think that was because there was somehow old code - but this was also preventing the warning message from being displayed.
refactor page-leave-warning on unsaved edits

* removed usage of prototype
* extracted code into separate file
remove usage of link_to_remote_if_authorized
remove usage of prototype in toggle_link
refactor _tabs.html.erb to meet our coding guide
Moved showWarning method back to container directive.
remove prototype usage in tab js logic

also extract the tab handling into a separate file,
which is included in application.js.erb
Merge pull request #1225 from opf/fix/timelines-show-warning-7186

Moved show warning method to timelines controller.
Avoid chart duplication on timeline updates on modal.close


Fixes #7247
Restore outline level when reloading timeline on modal.close
Merge pull request #1231 from opf/fix/timeline-updates-7247

Avoid chart duplication on timeline updates on modal.close
Merge pull request #1226 from opf/fix/maintain-back-url-after-bulk-edit-5841

Fix/maintain back url after bulk edit 5841