add utils file
add csv data descriptor
add sql data descriptor
add json data descriptors
add hdf5 data descriptor
default DataDescriptor.__init__/__getitem__
add interactions tests
csv->sql->json test
fix data imports
refactor common functionality into data.core
add python data descriptor
dshape, schema ensure datashapeness
pull out csv logic from CSV(DataDescriptor)
from future import ...
remove excess line
add simple dynd data descriptor
data descriptor docstring
data append checks appendable, immutable
JSON is not appendable, JSON_Streaming is
JSON is immutable, JSON_Streaming is mutable