Optimized the selection of random dungeons with weights applied. We now
have a class called WeightedContainer for taping into Minecraft's
weighted selection code without having to extend the WeightedRandomItem
class. Using that, we no longer need to keep a list with duplicate
dungeons to achieve weighted selection, so I removed that variable.
Moved all configuration variables from mod_pocketDim to DDProperties
(formerly DimDoorsConfig). Changed property names to be clearer in
config file, modified some comments, and generally cleaned up the config
file. Fixed some missing properties and variables that were reading from
the wrong properties. Modified the order in which mod_pocketDim
instantiated some of its static fields so that they would load after
properties are read. Almost all classes load after properties are read.
Fixed indentation across various files and replaced references to
properties in mod_pocketDim with references to DDProperties.
