factored common initialization code out
added time test (broken)
added allow_invalid_dates to dsn in time test (still broken)
improved structure (but still broken)
missed a truncate, tests pass now
drop collation statements in create, drop charset in create where not text
applied most change requests (missing err handling in Scan)
readded fail
removed line breaks
Merge pull request #57 from arnehormann/master

refactoring of driver_test.go