Mineclone2 support update

Minor bugfixes, including an update to support recent Mineclone2 versions.

Ambience, Achievements, and Mineclone support

This is a bugfix release that fixes a rare crash if the player lingers in the 1-node-thick boundary layer between layer2 and layer3 in the bloodthorn/nethercap biome.

Also added some API documentation.

Ambience, Achievements, and Mineclone2 support

• Fix undeclared local
• add group food_sugar to sugar, remove group stone from slade_drill

Ambience, Achievements, and Mineclone2 support

Bugfix for Ambience, Achievements, and Mineclone2 support.

• fix crash when mesecons mod is installed with default game
• remove flora group from underground plants

Ambience, Achievements, and Mineclone2 support

This release has a lot of changes under the hood to allow cross-compatibility with Mineclone 2. Mineclone 5 support is pending a pull request to that game's repository.

In addition, several new features have been added. Most significantly: there are ambient sounds that play in the various subterranean caverns that correspond to the biomes they contain, and a set of achievements have been added based on the "awards" mod.

Pit caves

Added the "pit_caves" module, which generates sparsely distributed very deep natural shaft caves.

Chasms

Added chasms and giant spider webs.

v2.1: Merge pull request #17 from FaceDeer/ground_covers

Accumulated tweaks and bugfixes, as well as several new minor features:

• New ground cover types
• Guardian statues in the Underworld
• Glowstone veins in the Primordial layer
• Limit fire spread in the Primordial layer
• hunger_ng support, with a few new edibles in Primordial layer

Primordial cavern layer

Various bugfixes to existing cavern layers, and the addition of the all-new Primordial cavern layer beneath the Underworld.

v1.0: Small stuff (#8)

Last release before Primordial cavern layer was added