Switching between --global-docks and --use-docks causes problems

[Edward K. Ream]

When switching between using the --global-docks and --use-docks command-line options, Qt gets confused about layouts. The easiest solution is to clear .leo/db.

I doubt that this can be fixed. Most of the relevant code is Qt magic.

This is a minor glitch. Most Leonistas will use one or the the other command-line option exclusively.

I have just created #1529 to memorialize this buglet.

Edward