Wrote separate method to pick a random value based on
constraints, bounds and DatumType - WorldTree.pickValue
This commit updates init.properties and world.definitions
It also removes them from the index

This commit ensures that some changes are lasting despite rebases
Added com.collection.range package

This package consists of classes that implement the concept of
Ranges

Consists of two classes that extend the abstract class Range
    - IntegerRange
    - FloatRange

Currently, Ranges allow the following functionality
    - contains
    - intersection
    - add

Range addition currently works only for the same types

PropertyDef.RandomSpec now uses Range class
Updated Parser and WorldTree to reflect this change