Add an annotation 'inline' to a text

[rgrp]

As A

User

I want to

Add an annotation to a text

So that

There is a new annotation viewable by other users

Notes

• The annotation should be addable 'inline' that is on the same page as the text so that a user can highlight the piece of text to which the annotation relates

[rgrp]

Annotation working as of r119. Several substantial issues still remaining (e.g. dealing with large texts but these will be made into separate new tickets). This was a huge new feature (probably should have been broken down further) and so this single commit only represents the culmination of work of a lot of work since December (including development of standalone annotater package: browser:annotater)