Allows the initial hand registration to alter the 'wield_scale' without
needing to also alter it in creative mod.
Also make default mod a dependency again, as the initial hand
registration is required.

Previously, the value of 'mapgen_limit' was not used to limit the
spawn position.
If a friendly-biome spawn point is not found within a small world,
spawn point falls back to the engine spawn point, which has a larger
chance of success.

The output returned by `get_craft_result` has a replacements table that
contains any replacement items that could not be placed in the input
(due to the input stack having a count > 1). Put these replacements in
the dst list or drop them on the furnace.

This prevents a crash when a 'nil' digger is passed by the engine to
minetest.node_dig.

Engine change now makes this possible.

Tune noise to appear roughly where long dry grass is least dense and shortest.

Fixes bugs caused by removing 'default' as a hard dependency.

Update side texture to match the new top texture.
3/4 side coverage instead of 1/2,

Enable colored Luacheck output on Travis CI

see #2400, also removed a now unused alias

Code simplification by combining the on_place functions.

sfinv: Add lists above the content to support listrings in content.
Reuse sfinv inventory lists for creative.

Icesheet ice dungeons now have ice stairs.
Remove some now-unnecessary sandstone mapgen aliases, one
remains as it is required by the dungeon loot mod.
Re-arrange mapgen aliases to separate those needed for mgv6.

This schematic is used for sapling-grown large cacti, so should not
destroy the sand node below, as sand nodes are in short supply in
some situations.
Like trees, only force-place the node that replaces the sapling.

The author is used to track packages for updating, so it should match.

No longer use the hardcoded engine cave liquids.
Water only in '_ocean' biomes, water and lava in '_under' biomes.

Previously, opening a trapdoor caused the side textures to flip.

Fix the incorrect textures.
Also add a texture transform to a tile of the open trapdoor, such
that the closed trapdoor sides use the lower part of the texture
and the open trapdoor sides use the higher part.

Clean up some codestyle issues.