SDL: set window title
Copyright update: 2013
Keyboard: shortcut pressing clear key
sam: fix CPU clock stretching

Transitions from fast to slow resynchronise with the VDG, so if an
odd number of fast cycles have run, extend it.
Fix switching from low RAM CoCo to Dragon

The RAM organisation flag was not being set appropriately.
printer: use a ROM intercept for CoCo printing

This should be replaced with proper serial protocol analysis when
available.
becker: fix const warning
vo_generic_ops: fix variable shadowing
ui_macosx: avoid left shift into sign bit
6809, 6309: use simpler sign extension method

Simpler, might not be faster.
6809, 6309 trace: use simpler sign extension method
cart: new cart instantiation code
events: avoid assuming 2s complement in tick comparison

Compiles to the same code on a 2s complement machine.
6809, 6309: remove cast to signed from irq cycle tests
6809, 6309: move state enum into header

For debugging purposes.  As a side-effect, 6309 code must use its
own state variable.
6809, 6309: remove unused halt_cycle
6309: fixup DIV* and MULD

MULD was actually wrong, the DIV instructions modified to use
fixed-width accesses to convert args to signed.
6809, 6309: misc int type tweaks
6809, 6309: offset _cycle when setting for cheaper compare later
cart: allocate initialised area for ROM