More simple chunk save predicate

[optim] Do not update EntityTracker if no players in world

Added PendingBlockUpdates and EntityFallingBlock processing and EntityItem removal after chunk populating ...

Newly populated chunk contains lots of PendingBlockUpdate and EntityFallingBlock, that takes lot of memory. PendingBlockUpdate processing causes more EntityFallingBlock spawning. In its turn, processing of EntityFallingBlock causes PendingBlockUpdate scheduling again. It solves by multiple iterations of processing both PendingBlockUpdate and EntityFallingBlock. Finally, we removing any EntityItem, that may be spawned at that time

Fixed /memstat "Off-Heap chunk used" more than 2gb

Fixed JLine tab completion

Issue #48 CPU utilization ...

Now we calling utilizeCPU method instead of Thread.sleep in in main server loop. In this method we can do something more useful than sleep. Currently implemented SyncServerExecutor queue processing and chunk generation

Fixed lots of issues with /genworld command

World generation limited to one chunk per tick

[optim] ChunkSendManager enhancements: ...

- min player moved distance is now directly proportional to viewDistance
- used back sort for toSend list (to remove values from end of list without copying)
- toSend list is now sorting only before sending (if necessary)
- removed unnecessary setWorldDestroyed method

[client] Fixed sending view distance to server when closing gui video settings by esc key

[refactoring] unused var & typos

Fixed chunk sorting with large view distance (> 15)

[refactoring] Var name typos

Fixed translation for server name in /say command

[compat] Fixed mod-supported interworld teleportation (MystCraft)

Max view distance is now 32 (15 by default)

Removed entity count from debug automessages

[compat] Compatibility with mods changes BlockLeavesBase (FastLeafDecay, DragonAPI)

[refactoring] Refactored ultramine class transformers

Configurable server directory mapping: ...

Returned vanilla logic of MinecraftServer.getFile; all vanilla files now gets by method getVanillaFile and mapped to ./storage by default. New system properties:
- org.ultramine.dirs.vanilla - sets directory for vanilla files, returns by getVanillaFile, default: storage
- org.ultramine.dirs.worlds - sets directory for worlds, default: worlds
- org.ultramine.dirs.settings - sets directory for ultramine configuration, default: settings
- org.ultramine.dirs.storage - sets directory for ultramine storage, default: storage

Fixed /memstat negative Off-heap used size & little enhancements

More correct bound chunks counting for ChunkGC

TileEntity onChunkUnload list processing moved before loadedTEList processing to prevent updating unloaded TileEntities

Fixed bug due to a009ef4: sometimes entities were removed from entityList, but not from chunk and tracker

[refactoring] World config applying code moved to public method in WorldServer

Issue #14 PlayerDeathEvent - allows to: ...

- set keepInventory flag
 - cancel drops processing
 - change death message

[refactoring] moved class UMEventFactory

Fixed block placement distance check - now relative to player eye location

Fixed reed dupe by door when block place event was canceled

Fixed InventoryUtil.dropItem with stackSize more than maxStackSize