Disable VisualEditor by default

If you enable MediaWiki-Vagrant's visualeditor role, then Flow will give
all users VE when editing board header and posts.  This avoids the
confusion.

Also fix whitespace (see https://gist.github.com/holysugar/1318698 !)

Change-Id: I85940964730e5d36da6d2506fd41ec048027b6da
Merge "Disable VisualEditor by default"