Add support for querying multiple catalogs via a table arg

[laserkaplan]

Basically the same as https://github.com/dropbox/PyHive/pull/246 but with a test added to showcase new functionality and a couple of fixes to resolve other bugs.

Many thanks to AlexandreOuellet for the original implementation!

[laserkaplan]

@bkyryliuk I'm hoping that you are still active enough to see this :) I have added a simple test to show the new functionality here. Please let me know if you would like to see anything else. It would be really great to finally get this into a release!

[AlexandreOuellet]

Thanks for the mention!

I'll try to reopen, update and correct my PR to pyhive so that it eventually gets in officially.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
3 out of 4 committers have signed the CLA.

:white_check_mark: AlexandreOuellet
:white_check_mark: VinceDPM
:white_check_mark: laserkaplan
:x: Aleandre Ouellet

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