eval_str handles date(time)s well
bcolz selection defaults to python on AttributeError
into: Iterator <- bcolz
python: datetime selection
bcolz selection python branch uses into rather than iter

This coerces types properly
deal with into conflicts and bcolz
fix eval_str doctest
separate selection functions for carray, ctable
Merge branch 'master' into nyctaxi-bcolz-fixes

Conflicts:
	blaze/compute/bcolz.py
Merge pull request #731 from mrocklin/nyctaxi-bcolz-fixes

Nyctaxi bcolz fixes