Add a unit-test to verify that when statements throw exceptions, the logger still has stopQuery called.

* allow hhvm/mysqli failure so poor travis can feel better

fixed typo

getSQLForJoins - infinite recursion if join alias is not unique

Close #777

Merge branch 'hotfix/#736-DBAL-1058-fix-database-and-namespace-introspection-for-sql-server-backport-to-2.5' into 2.5

Close #736