Implement virtual worlds
New schematic commands:
//schem show <directory>
//schem delete * - Deletes the files associated with your currently
loaded schematic
//schem move <directory> - Moves your currently loaded schematics to
this directory
//download -> supports downloading multiple schematics at once
Start work on command GUI
Code cleanup
Add new lighting mode (see config)
Rename sponge -> sponge112
Fix sponge compile issues
Fix fuzzy region min/max not being set on first use
Fix clipboard on disk not closing on java 9
Start work on CFI chunk simplifier (for loading existing worlds)
Minor tile fixes for bukkit 1.12
Start work on interactive commands (//help, //biomelist, //pos1/2)
Added clipboard and world remapping (between mcpe/pe)
//schematic remap
//anvil remapall
Added anvil -> leveldb converter (run Nukkit jar or /anvil2leveldb)
Added safe zstd decompressor
Angle mask fixes
Fix paste air issues with fawe format (which no-one uses anyway)
Fix cfi file:// with an absolute path
FIx schematic format and addBlocks
Update forge to 1.12
Fixes#663
