Vector and index reformulation

Purpose of code changes on this branch:

- Allow for optimizations for vectors holding double and integer values. 
Vector is now a generic interface of Number, whereas most current Vector
implementations are just a DoubleVector.  New vectors are IntegerVectors
for use in RI based sspaces.

- A new interface for vector generation and permutations.  There is also a
map interface which allows for the automation of index vector generation
based on use of a vector generator.

When reviewing my code changes, please focus on:

Possible implications of current design
Lack of clear JavaDoc

Please focus on the vector and index packages.  Others either have minor
changes based on these updates, or, like the clustering package, are not
quite finished being documented.

After the review, I'll merge this branch into:
/trunk
But first i'll reformulate the RI based code to use the updates checked here.

Original issue reported on code.google.com by FozzietheBeat@gmail.com on 6 Dec 2009 at 11:43

buliugu / airhead-research

Vector and index reformulation #38