Show all errors on link validation.

Switch to latest version of govuk_content_models which includes this fix, and
set Formtastic to use list format for inline errors to make the error text
readable.
Merge pull request #208 from alphagov/all_link_errors

Show all errors on link validation.
Start using admin gem

* Add govuk_admin_template
* Stop using less
* Remove jquery-rails, jQuery is provided via gem
* Stop using branches for formtastic, and use Bootstrap 3 versions
Switch to using govuk_admin_template layout

* Use nested layouts
* Make application.css SASS friendly, and import gem styles
* Remove now unnecessary javascript includes
Update to Bootstrap 3 grid classes
Put back bootstrap tweaks and overrides

* Switch from less to SASS
* Delete navbar less file, all styles are now in admin gem
Switch to Bootstrap 3 glyphicons
Buttons need a default class in Bootstrap 3
Compact publication filters

* Default bootstrap 3 styles make this slightly too big
* Compress the margins and reduce font sizes
* Split out into its own css file
* Don’t use grid classes in sidebar form, use form-control class
instead - it expands to 100% width by default
Remove unnecessary grid wrappers from publications
Give publications table header contrast

* Bring table inline with admin style guide
* Move sortable table styles into its own component stylesheet
* Darken the selected state (really the whole th cell should be
highlighted and clickable)
Use bootstrap 3 kaminari themes for pagination

* Pull themes from gem:
https://github.com/matenia/bootstrap-kaminari-views
Fix indentation on reports

* No need for any grid wrappers or classes here
* Remove row and column divs
Move edition labels beneath header

* Labels inherit their text-size now, this leads to labels being huge
if they are in an <h1>
* Grey labels also need a default class, “label-default”
Remove further grid wrappers

* Show and diff pages don’t need to be wrapper in a row class
Switch metadata to use bootstrap 3 form classes

* Use `form-control`, and move the grid wrappers from input to a parent
wrapper
Add spacing between tabs & tab content on editions
Tidy up edition history forms

* Remove unnecessary form wrappers
* Replace grid classes on inputs with bootstrap’s form-control
* Split two types of note with a horizontal rule
Change bootstrap grid classes for editing titles

* Instead of putting grid classes on individual form elements, use rows
and wrappers instead
* Removed specific CSS for the now unused “control-group” class (from
bootstrap 2)
Cleanup expectations view

* Remove outer grid wrappers
* Use `page-title` to avoid a border on the page header which clashes
with the bootstrap well