GXemul Code2

Avoid warnings with old GNU C++.

Use the ptrdiff directly.

20090804 Using anonymous unions and ptrdiff_t, to avoid overloading
pointers and size_t members unsafely, and other size_t usage.
(Thanks to Weinholt for commenting on this.)

Beginning on M88K bsr and jmp.n instruction implementations, and function call trace support.

Display all state change on variable assignment. (In the future, when variable write handlers work, a write may have side effects, and this will make sure that the user sees those state changes.)

Documentation updates.

Updating the Introduction chapter in the documentation with a section about the New framework.

Implementing a skeleton implementation for the backward-step command (but since variable write handlers aren't implemented yet, it doesn't really work).

Continuing on the dyntrans core loop (inlined instruction calls first, then run a few remaining calls).

Continuing on the dyntrans core loop; single-step, starting in delay slot, fault in delay slot, etc.