Enable the --single-transaction flag by default, it can still be disabled using the constant
Ignore the warning introduced in mysql 5.6 when connecting the database via cli with -pPASS

Fixes #275
We have to set both flags as setFlags overwrites previous flags
Add a new test data directory and file for the symlink tests and change the unit tests to assert the correct number of files
Assert that there are no warnings, not errors
Skip the plczip broken symlink test as it's a known failure
Correct order for assertEquals