Fixed piston code griefing damage.
Removed SetServerBlock griefing.
Implemented cWorld:QueueSetBlock(), as requested for delayed blocksetting.

Untested yet, so might not work.
Fixed crash when the player is above the world.

Fixes #53.
Removed an unused CriticalSection from cChunk.

Fixes #109
cChunk::SetBlock() now uses cChunk::FastSetBlock() for the common code path.
Implemented the OnWorldTick hook.

Triggerred for each world every time it ticks, parameters are the cWorld and the previous tick length (a_Dt)
Finished renaming cPlugin_NewLua to cPluginLua.
Fixed timed event wait on Linux.

Was causing an error message and the DeadlockDetect didn't work.
Moved entities into the Entities subfolder.
Added cPickup:GetAge() the the Lua API.