Minor Change

Autocorrected indentation in PocketManager. I'll be working on changing
PocketManager to prevent the risk of creating data for a non-existent
dimension through a bad call to getDimensionData().
Fixed Crash on World Creation

Fixed an issue. DD would crash when MC created a completely new world
because onChunkLoad() would be called before onWorldLoad(). That's not
the usual order. PocketManager would be unloaded at that point and would
return a null dimension.