* add changelog for postres source
* add changelog for mysql source
* add changelog for mssql source
* add changelog for file source
* add changelog for google sheets
* add full changelog for file source
* add full changelog for google sheet source
* add full changelog for mssql source
* add changelog for http requests
* add changelog for salesforce source
* add changelog for facebook marketing source
* add changelog for google analytics source
* add changelog for shopify native source connector
Release all connectors affected by namespace change. Includes all JDBC sources and destinations.
Also add documentation for normalisation. Prerequisite to actually releasing 0.21.0-alpha.
