gunzip/neonlib: Decouple reader from buffer and introduce supplier.

MappedLoader: Move gzip decompression from Application to MappedGzipLoader.

Also rename MappedBufferLoader to MappedFileLoader and make a few tweaks.

gunzip: Read decompressed data in blocks.

Rather than through callbacks to a writer. This makes it easier to process.

Mapped32KWriter and MappedBufferLoader now work without Writer.

gunzip/neonlib: Update to latest.

Fixes issue with decoder buffer overflow.

MoonSound: Simplify wave number mapping.

The new implementation does away with the mapping table, and instead just masks
the instrument number to the 180H-1FFH range.

The previous implementation effectively did the same, however it used a lookup
table in anticipation of a more complex mapping scheme which never materialized.

MoonSound: Fix playback of tracks with a ROM data block.

It would never actually call SafeWriteRegisterWave since Device_ConnectInterface
dereferences the jump as an optimisation. We use a jr instead to avoid this.

Application: Update to latest gunzip and neonlib.

Makefile: Output symbol file to gen directory.

Header: Clear past extra header offset (if specified).

Used in e.g. Misty Blue YM2608 version.

Header: Add helper function to get relative offsets.

Added tag release-1.4 for changeset d8cc9b9139e0

Application: Increase version to 1.4.

SoundStar: Add SuperSoniqs SoundStar support.

MSXAudio: Fix mute not setting key off correctly.

tools: Update Glass to version 0.6.

Darky: Save one byte.

Added tag release-1.3 for changeset d53f33dc6397

Application: Increase version to 1.3.

CHANGES: Set 1.3 release date and add Mercurial log link.

README: Add link to SourceHut issue tracker.