Reduced the clutter in collections package

Put the specialized ZArrays into ZArray class
Deleted WeightedIterator, since we no longer use RceCollections
Moved RandomElementChooser to collections package
Deleted BalBinaryTree - add it when I get around to making it
Continued testing for collections

Especially the ZArrays
Added support for varargs in MlList and ZArray
Removed MlListTest since it was simply a source of failing tests
Will readd it when making tests
Updated Matchers to work with std Matcher grammar

Matchers now make sense for using is() and is(not())
Updated DataChecker to work with varargs
Started Testing Stackable

Added test and functionality for UDie.name()
Added varargs ability for MlList
Started varargs ability for Stackable