Adding distinct expr node
Adding python distinct backend
Adding pandas distinct
Adding distinct to sql
Use iterators for unique and len in python backend
Add cytoolz to test installers
Fix imports
Make distinct it's own expr
Merge pull request #304 from aterrel/distinct

Distinct
compute: pandas By is much faster

We no longer rely on apply(lambda df: compute(t.apply, df))

We now precompute the apply, then compute the grouper, then perform a
join/groupby

http://stackoverflow.com/questions/23924888/pandas-groupby-series-with-dataframe
Fixing schema and doctest
get_py/dynd avoid needless cross talk
add `__all__` to compute files
Merge pull request #309 from mrocklin/faster-get

Faster get - also `__all__` to resolve import issues.
Merge pull request #308 from mrocklin/faster-pandas-by

Faster pandas by
remove dshape keyword from CSV
CSV schema discovery
discovery: hints for csv
SQLAlchemy table datashape discovery
SQL datashape discovery