[NEW] [WIP] #4466 Port settings pages to Bootstrap (edit profile, edit account, privacy, services)

Hey guys!

First of all, sorry for creating a new PR and making you do code review twice. My bad.

First attempt was a bit clumsy and I was really out of time, too busy at work to do things the tidy way. Now I have more time, and I'm happy with the results of this one, really clean.

I ported all of the changes from the old PR to this new one, manually, taking all of your comments / observations into account. 

Let's see what Travis says and review.

I'll comment the old one so you can freely delete it.
You only want to apply this to the actions you switched to bootstrap too. I'm not 100% certain but try if this leaves the switch at ApplicationController in place for the other actions:

```ruby
layout -> {...}, only: [:show, :edit]