Issue 1331 - Correct formatting on home page button and refine behaviour for logged in users when invitations are not required.
I think this is what we want
green for staging
Once more with feeling
Issue 1331 -  Rationalise buttons on home page, refactor tests
Merge pull request #1771 from ariana-paris/Issue-1331-Home-page-buttons

Issue 1331 - Invite a Friend button on home page
Merge pull request #1772 from zz9pzza/issue_4031

[Issue 4031] I think this is what we want