Remove it from the script info section and put it in its own section
that isn't tracked by undo and make it not stringly typed. Removes the
need for the gross hack where changes are slipped in just before saving
to circumvent the undo system, cuts down on the uses of string literals
to identify fields, and probably improves performance a little.
Since luabins generates binary data which grows up to 3x by escaping,
it's more efficient to uuencode that instead.
A marker is placed as the first character of the value field, either
'e' for inline_string escaped text, or 'u' for uuencoded binary data.
The key is always inline_string escaped, as it will typically be
human readable.
