Changing up block/chunker/encoding to use numpy arrays
First rounds of using numpy uint64 xoring
Changed file encoder to use with enter and exit methods
Changed decoder to work with numpy arrays
Altered test to use the new 'with' context on the file chunker
Stopped padding source files prior to decoding.  Incomplete symbols are filled into a numpy array from a padded string instead
Added ability to detect 32bit vs 64bit systems and to create numpy arrays of unsigned ints accordingly
Changed raptor's numpy xors to use the 'to' parameter