Begin Special:UserProfile overhaul

* Temporary add MORE grays
** Yet introduce @grayMid, @grayDark and @grayLight variables
to avoid introduction of yet another tone of gray. It's expected
that we can standardise on our grays at a later date using these
variables, changing where necessary.
** Only show section when there is a contribution

Change-Id: I168f5faa11c58a93691f10807491accedc865143
Merge "Begin Special:UserProfile overhaul"