Bug 966839 - [Camera] Add frame grid to camera settings
Enables settings but disable all options except grid
Swaps rows and columns
This commits makes the video rotate instead of the whole viewfinder frame.

This simplifies the implementation of the grid since it doesn't have to account for the rotation anymore.
Cleaning up css
Creates container around the video element to decouple the preview stream and the grid
Closing settings menu on selected option. As defined in the UI specs
Removes unnecessary dependence
Replacing pixels with rems
Removes unwanted borders along the edge of the screen