DGen 1.28

Another major release!

- Use libarchive (when available) for ROMs decompression.
- The "tobin" utility has been renamed "dgen_tobin".
- Fixed CZ80 emulation bug from v1.27 (weird sound).
- Improved runtime switching between CZ80 and MZ80.
- Improved save files handling, they are now compatible with Gens v5.
- YM2612 emulator has been upgraded from version 0.35f to 1.4b.
- Improved sound buffer management (again).
- 8-bit sound output support has been dropped.
- Game Genie codes can now be entered while in stopped mode.
- YM2612 and SN76496 clock frequencies have been corrected.
- There's a new command-line option to select the console region.
- OpenGL output now uses a single, bigger texture instead of two.
- As usual, many other bugfixes.