Pull job/repository actions out of cog menu.

It's very hard to notice where something is, when it's hidden in
that menu.
Pull some bindings into build and job controllers.
Disable links when permissions isn't granted.
Make action links actual icons.

This change pushes the cog menu to the top, where it belongs, as it
now only includes repository-relevant actions. The icons now reflect
things relating to the build/job itself, and have replace the cog
meny.
Merge branch 'mm-extract-actions-from-menu'