Enable/disable building of QA views (refs #7545)

Adds a new configuration option, `CouchDb.SyncQAViews`, read by the sync_couch_views.py script. The `Couch().sync_views()` method now also accepts a `sync_qa_views` argument.
Yes, it should be True.  I'd normally want to have it throw errors for undefined settings, but this thing seems like more of a stopgap measure until we can do something one way or another with the Couch views, thus making the setting optional, and falling back to a default.