Review/Internationalise Capabilities and Descriptive Text for Consistency Prior to Release

[Daniel Marsh-Patrick]

The capabilities needs another pass to ensure that field names and descriptive text is up to date for all current features.

As part of doing this, we'll also add the display/description keys for en-US, ready for any potential internationalisation efforts down the line.

[Daniel Marsh-Patrick]

Moved capabilities into en-US language files and reviewed assistive text and labels. Gives us a framework for internationalisation of these items (the code will be done in 1.4). Resolves #82

→ <<cset 7bf9fc50a3ba>>