Feature/stream name root table canonicalization

[AlexanderMann]

Motivation

#102

• Provide logic which works in target-redshift as well as target-postgres
  • works across all versions
• Migrates existing remote databases seamlessly
• Existing tests remain untouched

Notes

This will break instances where multiple versions of target-postgres are trying to upsert different streams (taps) to the same remote.

I'm unsure as to whether we want to support this use case.

ie, as a user, I have a long running tap persisting data to postgres db A, via target-postgres v0.1.8. I also want to be able to run the latest target-postgres v0.1.X to persist another tap to db A.

Suggested Musical Pairing

https://soundcloud.com/snottynoserezkids/sets/snotty-nose-rez-kids-lp

[AlexanderMann]

Of note: I realized recently that we assume all the time that there is only one target running per db all the time. This is due to us using transactions on the db, so something should just fail quickly if there's a conflict etc.