GXemul Code2

Adding another Dreamcast screenshot: the gltest from the KOS examples.

Various Dreamcast and/or SH4-related updates.

Found a bug in the SH4 fsca instruction: the angle argument for sin and cos was incorrectly calculated. "dcfighting.bin" and "gltest.bin" (two "homebrew" Dreamcast programs) now look much more like on the real Dreamcast.

Continuing on Dreamcast and SuperH emulation: the SH4 DMA channel numbers were off-by-one (but did not really have any negative effect). Experimenting with end-of-DMA mechanism in dev_pvr. Adding a second device thing at 0x005f7c00, which seems to be a PVR DMA register range, but not much used?

Adding "trace" versions of SuperH bsr and bsrf_rn instructions. Adding the first SuperH instruction combination for speeding up a variable read loop (bt_samepage_wait_for_variable).

Fixing bug at end of address space, which caused symbols to not show up.

Adding missing Dreamcast entry.

Better reset of graphics during "switch to bootstrap 1" in Dreamcast fake ROM emulation.

Show symbols in more cases than before.

Adding Dreamcast devices as symbols, so that runtime debugging will show meaningful names instead of just addresses, when reading and writing device registers.