Updated documentation for non-unique label changes. Added a new
section to tutorial #1.
Updated examples to use non-unique labels and variable tables.
Tweaked the EditLabel radio button names.
Continue development of non-unique labels. The actual labels are
still unique, because we append a uniquifier tag, which gets added
and removed behind the scenes. We're currently using the six-digit
hex file offset because this is only used for internal address
symbols.
The label editor and most of the formatters have been updated. We
can't yet assemble code that includes non-unique labels, but older
stuff hasn't been broken.
This removes the "disable label localization" property, since that's
fundamentally incompatible with what we're doing, and adds a non-
unique label prefix setting so you can put '@' or ':' in front of
your should-be-local labels.
Also, fixed a field name typo.
