* magicform is a helper package that may eventually be part of the go/ui
library, for easily creating structured form layouts.
* The Level Publisher UI is the first to utilize magicform.
Refactor how level publishing works:
* Level data now stores SaveDoodads and SaveBuiltins (bools) and when
the level editor saves the file, it will attach custom and/or builtin
doodads just before save.
* Move the menu item from the File menu to Level->Publish
* The Publisher UI just shows the checkboxes to toggle the level
settings and a convenient Save button along with descriptive text.
* Free versions get the "Register" window popping up if they click the
Save Now button from within the publisher window.
Note: free versions can still toggle the booleans on/off but their game
will not attach any new doodads on save.
* Free games which open a level w/ embedded doodads will get a pop-up
warning that the doodads aren't available.
* If they DON'T turn off the SaveDoodads option, they can still edit and
save the level and keep the existing doodads attached.
* If they UNCHECK the option and save, all attached doodads are removed
from the level.