This is the first step toward changing the address region map from a
linear list to a hierarchy. See issue #107 for the plan.
The AddressMap class has been rewritten to support the new approach.
The rest of the project has been updated to conform to the new API,
but feature-wise is unchanged. While the map class supports
nested regions with explicit lengths, the rest of the application
still assumes a series of non-overlapping regions with "floating"
lengths.
The Set Address dialog is currently non-functional.
All of the output for cc65 changed because generation of segment
comments has been removed. Some of the output for ACME changed as
well, because we no longer follow "* = addr" with a redundant
pseudopc statement. ACME and 65tass have similar approaches to
placing things in memory, and so now have similar implementations.
64tass wants to place its output into a 64KB region of memory,
starting at the address "*" is set to, and continuing without
wrapping around the end of the bank. Some files aren't meant to be
handled that way, so we need to generate the output differently.
If the file's output fits nicely, it's considered "loadable", and
is generated in the usual way. If it doesn't, it's treated as
"streamable", and the initial "* = addr" directive is omitted
(leaving "*" at zero), and we go straight to ".logical" directives.
65816 code with an initial address outside bank 0 is treated as
"streamable" whether or not the contents fit nicely in the designated
64K area. This caused a minor change to a few of the 65816 tests.
A new test, 20240-large-overlay, exercises "streamable" by creating
a file with eight overlapping 8KB segments that load at $8000.
While the file as a whole fits in 64KB, it wouldn't if loaded at
the desired start address.
Also, updated the regression test harness to report assembler
failure independently of overall test failure. This makes it easier
to confirm that (say) ACME v0.96.4 still works with the code we
generate, even though it doesn't match the expected output (which
was generated for v0.97).
(problem was raised in issue #98)
