Correct selection as per browser behaviour

I'm assuming the browser actually selects the contents of the P, not the P.
Insert BR elements when content is only a Scribe marker
Update expectations now that we append BR elements to inline elements that contain Scribe markers
Tidy up
Tidy up
Fix broken tests for undo manager now that we append BR elements to inline elements
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Merge branch 'master' into oja-tests

Conflicts:
	src/plugins/core/formatters/html/ensure-selectable-containers.js
Merge pull request #224 from guardian/oja-tests

Fix broken tests