Some URL cleanup.

Link to section instead of section keyword e.g. /books/books

Do not put hreflang links on 'all' pages of sections.
Fix the last edited heading in collections

Last modified time shows as 'x days ago ago'.
The commit also introcudes a way of running unit(?) tests for knockout.
The spec loads a mocked list of fronts, collections and items and starts the application.
The test is trivial, it just asserts the text of an element, but it can be extended in the future to run assertion on user interaction.
Remove unused raven references
Wrap and tag video errors
catch sharecount errors caused by ghostery
more descriptive error message
Merge pull request #7041 from guardian/typo

Fix the last edited heading in collections
show linebreaks in comments
increase discussion min-height to avoid overlap
discussion avater stylefix
Merge pull request #7047 from guardian/handle-media-errors

Handle media errors
Hover on the video controls keeps them visible
Merge pull request #7033 from guardian/section-links

Some URL cleanup.
adding collapsable ad size to galleries
Merge pull request #7053 from guardian/collapsable-for-galleries

Adding collapsable ad size to galleries
Merge pull request #7051 from guardian/video-controls-hover

Hover on the video controls keeps them visible
Merge pull request #7050 from guardian/discussion-overlap-fix

Fix discussion overlap
Merge pull request #7049 from guardian/discussion-linebreaks

show linebreaks in comments
Merge pull request #7048 from guardian/ghostery-sharecount

Fix for Ghostery + sharecount
Merge branch 'master' of github.com:guardian/frontend into merge-facia