STY : removed duplicate import
WIP : draft of sparray (GridData) extension to ndarray

 - contains _a lot_ of debugging print statements
 - partially functional
WIP : work on classifying what ndarray function need wrapping
WIP : added down-cast on methods that do not preserve shape

 - added tests for most down-casting functions
 - not-implemented reduce based functions (which seem to down cast
   on their own if __array_finalize__ raises an error)
DOC : added draft of constrained data types
WIP : added wrapper function for function run through reduce

 - likely still buggy,
 - needs tests
WIP : more work on getting all of the reduce functions to work

 - added simple tests to make sure that results match numpy
 - need to add tests that axis information getting transformed
   correctly
 - 4 failing test (cumsum and cumprod)
WIP : fixed cumsum/cumprod failures

 - ptp is a special snowflake
PEP8 : in tests
WIP : Added data_unit to sparray

 - this is the unit of the voxel values
 - maybe want to get rid of explicit `label_data` flag and replace
it with a property that sorts out the bool value from looking at the
unit
 - need to sort out if this is a string or an object
WIP : renamed sparray -> GridData

 - match the data modeling documentation
STY : removed un-used import
STY : house keeping, organization, and comments
STY : renamed dtypes.txt -> dtypes.org so org-mode auto-works
added dtype notes
Merge pull request #5 from tacaswell/core

Core