Dialog component

A Dough module to allow the hiding/showing of a dialog 'window'.
I think it's better we split up this file in multiple views. 

Something like this structure:

stylesheets/
   - index.html.erb
   - _dialog.html.erb
   - _popover.html.erb
   - ...

The benefits. This large file doesn't complain when rebasing a lot of times, we can search for the component in the editor just typing in the name. You can make in an other PR if you like. If you want I can help on this. @ourmaninamsterdam wdyt?