Clean up and modernize Tile tool code

I didn't realize the previous version was in such bad shape.  It hadn't
even been given the latest text up/down user controls - it was still
using manually synced scroll bars and text boxes!  My bad.

The new version is much smaller and cleaner than before.
Finish command bar work

Fixes #67.
Fixes #68.
Fixes #75.

IT'S FINALLY DONE!  All tools now save/restore last-used settings.  All
support saving/loading presets.  All have a "reset to default" option,
and all can be randomized.  This was a huge task, but one well worth it.
Program-wide usability has been significantly enhanced by it.

Two holdouts are the Resize and Canvas Resize tools.  These are a bit
tricky, as we don't want them automatically loading last-used
settings... so I'll need to add a new property to the command bar to
handle that possibility.  I'll have that done in the next few days.