Revert "test env fix"

This reverts commit 012f11c295a51429c553a7066f73204602b71b37.
Tear down the environment only once for querysevice_test.py.
Fixing mysql_binary_path.
queryservice: support qualified column names for update statements
Merge branch 'vtocc'
queryservice: log normal errors as warning

Since normal errors are common, it's better to log them
as warning.