Added heuristics for reorderings within basic graph patterns
Changes for pushing simple numerical filters down to HBase
Moved to optimizer.reorder package
Further adaptations for using the new FilteredTriple
Added machinery for a pushing a filtered call down to HBase + code
cleanup
Related to cleanup from previous commit
Changes for pushing filters to HBase
Bug fixes for pushing down predicates
Filter fixes ; added a cache for storing intermediate bindings
Changes towards eliminating materialization of Ids from subqueries
Further refactoring for doing late materialization of HBase ids
Renamed util package + refactoring
Added functionality for materializing Ids after resolving a basic
graph pattern + proper naming of some classes
Partial functionality  for mapping Nodes to NodeIds before resolving a
Basic Graph Pattern
Finished materialization at BGP level
Encoded a NodeId as a Node_Literal in which the Id takes up the label
field
Fixed bug related to Optional clauses crashing
Fixed crash for empty result rest
Separated into a new object machinery code for mapping between Value
objects and Ids at the Graph level
Code cleanup