Give an error for old protocol version.
Special handling of error message to V2 client.
Add an IT for that.
Include bad message in failure report.
Need to use the version that waits for the server to be running.
merge MMcM: Check for unsupported Postgres protocol version and give explicit error

Merge pull request #1030 from MMcM/sql-layer/pg-reject-old-ptcl-version
https://github.com/FoundationDB/sql-layer/pull/1030