Add support for toggling column visibility

This adds support for toggling the visibility of individual
columns in the main table view. Now, the user can right-click
on the column header and hide or show each column.

Change-Id: I628e5b704e9db6fa65f2e4daaa7b1d4dc9223fbf
Merge topic 'toggle-column-visibility' into master

62d0454c Add support for toggling column visibility