v0.4.2

Release Notes

• Improvements to ZQuery, including a simplification of DataSource that no longer requires a Service by @adamgfraser. See #160 for details.
• Fixed the encoding of error messages by @paulpdaniels (#145)
• Documentation improvements by @phderome
• Updated akka-stream to 2.6.1
• Updated fastparse to 2.2.2
• Updated magnolia to 0.12.6