v0.4.0
* Fix panic due to inconsistent label cardinality when using queries.yaml with queries which return extra columns. * Add metric for whether the user queries YAML file parsed correctly. This also includes the filename and SHA256 sum allowing tracking of updates. * Add pg_up metric to indicate whether the exporter was able to connect and Ping() the PG instance before a scrape. * Fix broken link in landing page for `/metrics`