add rudimentary dynd backend
add dynd to front imports
start h5py compute layer
Merge branch 'master' into dynd
Merge branch 'master' into h5py-compute
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
rename test_dynd to test_dynd_compute
move resource from api to top-level
move drop and create_index to blaze/resource
import dispatch from blaze.dispatch, not multipledispatch
uri dispatched drop/create_index functions
use strtypes in resource.py
replace basestring with strtypes