ensure align = left is the default and update documentation accordingly

fixes #1403
Improve error message when a full_text property is missing
i3bar: Respect the urgency flag on status blocks

…by drawing urgent blocks with the same settings as an urgent workspace.

(Also use logical_px() and bar_height.)

fixes #682
Prevent workspace change during global fullscreen

While in global fullscreen, the workspace could be changed leaving the
fullscreen container still visible on top but losing its focus.
Extend the fullscreen command

Rather than just toggling the fullscreen modes, allow to set them
directly with:

    fullscreen enable|toggle [global]
    fullscreen disable

For compatibility, retain the previous command and its toggling behavior:

    fullscreen [global]

fixes #1120