Updated the readme with further instructions

on how to configure and run the tests against a local dev-build instance.
Update readme.md
created a table of contents
Hide most popular video component on children's books
Provide tag combiner href in Video in Section
Use full sectionTag
Provide an endpoint that allows client to specify a series id for exclusion
Update the video section routes
Change more in section endpoint depending on if there is a series
Use section id rather than section name
handle search box position on very large screens
Add onward section videos tests
Merge branch 'master' into video-last-touches

Conflicts:
	common/app/conf/switches.scala
quick fix for edition selector
hide 'subscribe' on tablet and below
Merge pull request #5373 from guardian/header-fixes

Blue header bug fixes
Merge pull request #5357 from guardian/video-last-touches

Video last touches
Update readme.md
Added link from root readme to integration test
Merge pull request #5286 from guardian/test-automation-readme

Updated the readme with further instructions