0.6.5: Dependency Fix

PyTables is not used directly by ivert, but is used by Pandas when saving results database files upon the "activate" command. Added tables (PytTables) dependency to package in PyPI and Conda Forge.

What's Changed

• Add tables (PyTables) to dependencies by @mmacferrin in #54

Full Changelog: 0.6.4...0.6.5