add images for the sub-panels
Use subpanels to display users and dial-in form
Put the tabs on the right.
Let login view handle logout in subpanels
style the disconnection panel
Sync with master.
Move contacts import and feedback in the gear menu.
Wait for subpanels to be visible.

(Since #signout is now inside a subpanel)
Click the gear menu before logout
Better style for the #login button
Add a static dialpad image to the 'dial' subpanel
Refactor subpanels
Split tabs into more than one view.

This allows more readability of the code.
Part of this commit also renames the #settings tab into #gear-menu because
that's how we call it.
Add tests for the subpanel view / gearmenu view
Rename SPAView in DialInView
Rework the Subpanel view to include its pans.
Sync with master
better styling for the instantshare link
fixed minor issues with styles & html
updated SubPanelsView#render to return early