fixed quoting of non-string session vars
added todo
removed unused use-statement
added test to detect the root cause of the Iterator test that breaks on Travis (#30)
fixed key() handling (#30)
test helper throws exception now as markTestSkipped() is not available anymore
added configuration conversion test (#30)
added session parameter conversion (#30)
improved comment
extracted connection configuration (#30)
createConnection() validates and normalizes the connection options now; this is important as the tests use this method on its own (#30)
improved connection creation; validation is performed only once now (#30)