Ignore some non-logical schema based values and use textual representations instead.
Make "--filter" logic to honour regular expressions

Uh, this is tracking head of my fork, sorry about that. Changes as of 18da30e are as follows:

• Fixes: check_same schema
  • support checking across logical replicas by checking logical name/type/definition when comparing operators/indices/functions/triggers etc rather than oids
  • add '--assume-async' option to skip checking sequnece last_val on asyncronous replicas
  • stop picking up oid named deferrable unique constraint triggers in trigger check
  • correctly identify objects owned by group roles
  • allow constraint check to work across <= 9.2 and >= 9.3 (pg_constraint.confmatchtype = 'u' == 's')
  • include table name in key used to identify trigger and constraint checks to prevent false positives
• Fix: --filter on regex (as per the manual) rather than equality
• Fix: stop replicate_row returning "Cannot test replication: values are not the same" when repinfo vaues = "0"
• Fix: stop check_locks returning "No matching databases found due to exclusion/inclusion options" on quiet database with no locks.
• New check: check_replication_slots to check retained xlog for all/specific slots
• Other cherry-picked commits from other forks
  • Application name exclude for transaction_time / transaction_idle (martinmarques)
  • Correct query_start == state_change for PG 9.1+ (sebastianwebber)
  • Fully qualified names and MIN/MAXPAGES in check_bloat (martinmarques / moench-tegeder)