v0.4.1 Support pgbouncer v1.16

• update default collectors
  • omit citus & timescaledb schemas on object monitoring
  • avoid duplicate pg_statio tuples
  • support pgbouncer v1.16
  • bug fix: pg_repl collector overlap on pg 12
• new parameter: -T connect-timeout PG_EXPORTER_CONNECT_TIMEOUT
  this can be useful when monitoring remote postgres instance.
• now pg_exporter.yaml are renamed as pg_exporter.yml in rpm package.