The migration was broken into one migration per table to reduce table locking and reduce the
chances of failure due to SQL timeouts.
Of the 14 fields that lacked time zones, only the 3 named 'interval_start` seemed to have non-UTC data in them.
These fields are fixed in the migration by removing the +00 and adding AT TIME ZONE current_setting('TIMEZONE')
Field with good data are migrated by adding AT TIME ZONE 'UTC'
Note that postgres's timezone() is different than cockroach's timezone() so AT TIME ZONE is used.
https://storjlabs.atlassian.net/browse/SM-104
Change-Id: I410f2f1d7c11b143f17844347f37e6f4b1e70fce
