R1:800aa92fd9be

Refine "Tactical Command" layout and styling

Summary:
- Move the buttons in the jump nav to iOS-style "application" buttons in the
header. These are sort of ugly right now, but I think serviceable enough. Some
day we will hire a designer whose entire job is to pick up after me.
- This gives us more room (allowing us to restore "Maniphest" and
"Differential").
- This also disassociates the app buttons from the jump nav, which was a
point of confusion (user expectation that the text input is…