Change title 'Lightweight Activities' on home page to 'Activities'.

[#47150075]
As per https://www.pivotaltracker.com/story/show/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'.
tooling: update schema, add /bin to gitignore, --create gemset in rvmrc.
Update hostnames in deploy/* files. (authoring.concord.org &etc.)

[#47150075]

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