Add bqjdbc URL/connection builder test utility

[goomrw]

bqjdbc connections are configured via URL parameters.
Tests configure their connections with string literals which is very error prone (what if a parameter is listed twice? what if there are two &?)

We should write a utility class that constructs URLs at a higher level to eliminate these issues. We might consider a ConnectionBuilder to manage the creation of connections.

See:

          maybe there should be a ConnectionBuilder that removes all this JDBC Url crap from our own tests ?

Seems like an obvious way to cause bugs.

Originally posted by @fzakaria in #186 (comment)