sql: discover(metadata)
sql: compute_up(Field, MetaData)
sql: post_compute(MetaData)
Merge pull request #879 from mrocklin/sql-metadata

Support computation on sqlalchemy.MetaData objects
expr: lean projection on Merge
Merge branch 'master' of github.com:ContinuumIO/blaze
lean projection on label, relabel
Merge remote-tracking branch 'ContinuumIO/master' into replace-into

Conflicts:
	blaze/compute/sql.py
	blaze/sql.py
	blaze/tests/test_sql.py
add into to requirements