CLN: make cleaner for debugging
CLN: clean up a bit in pytables
CLN: add _ensure_decoded to common
CLN: clean up pytables some more
CLN: remove debug cruft
ENH: allow parsing of datetimes
ENH: give visitors their own term and const type class vars
TST: smoke test for datetimes
TST: remove query test and put in test_frame.py
ER: add NameResolutionError, a NameError subclass
CLN/ENH: add syntax check before name resolution attempt
TST: flesh out testing for isexpr
CLN: move query to its own test class and add scope tests
ENH: ensure that resolvers do not overlap with current scope