Altirra 2.4 test 13.

Fixes a crash and a couple of small emulation bugs with XEP80 support, adds XEP80 support for error hovers, adds some on-screen indicators for display changes, and adds an "extract boot sectors" command for use with bootable virtual folders.

Did some tests with joystick support, but wasn´t able to reproduce the joysticks suddenly stopping working. One thing that would be useful to know is if the people who are experiencing this problem are using input maps that are bound to a specific game controller, or if the input maps are just set to Any controller (default for all built-in maps).

thanks Avery !