Remove "Lightweight" from the title, as per: [#47150075]

Change lightweight authoring url from lightweight-mw.concord.org to authoring.concord.org, and change title that says 'Lightweight Activities' on the home page to 'Activities'.

https://www.pivotaltracker.com/story/show/47150075
Fix: Activity's "related" displays even when its value is set to nothing

was: An activity's "related" text can't be made empty (and therefore can't be hidden)

[#46987287]

https://www.pivotaltracker.com/story/show/46987287