Changed basic data item from an "extended enum" to a class, so we can
keep track of where things come from (useful for the display list).
Finished edit dialog. Added serialization to project file.
The tool allows you to cut a piece out of a file by specifying an
offset and a length. A pair of hex dumps helps you verify that the
positions are correct.
Also, minor cleanups elsewhere.
The ability to give explicit widths to local variables worked out
pretty well, so we're going to try adding the same thing to project
and platform symbols.
The first step is to allow widths to be specified in platform files,
and set with the project symbol editor. The DefSymbol editor is
also used for local variables, so a bit of dancing is required.
For platform/project symbols the width is optional, and is totally
ignored for constants. (For variables, constants are used for the
StackRel args, so the width is meaningful and required.)
We also now show the symbol's type (address or constant) and width
in the listing. This gets really distracting when overused, so we
only show it when the width is explicitly set. The default width
is 1, which most things will be, so users can make an aesthetic
choice there. (The place where widths make very little sense is when
the symbol represents a code entry point, rather than a data item.)
The maximum width of a local variable is now 256, but it's not
allowed to overlap with other variables or run of the end of the
direct page. The maximum width of a platform/project symbol is
65536, with bank-wrap behavior TBD.
The local variable table editor now refers to stack-relative
constants as such, rather than simply "constant", to make it clear
that it's not just defining an 8-bit constant.
Widths have been added to a handful of Apple II platform defs.
