Fixed a potential Out of Bounds (OOB) issue related to escaping large queries. (Bug #36955942)

The internal mysql_init() function used for making connections is now thread safe. (Bug #115710, Bug #36894687)

With the prefetch connection option set to a non-zero value, large queries could cause the connector to unexpectedly halt. (Bug #113554, Bug #36945554)

Fixed the SQLBulkOperations() function's generated WHERE clause, which could potentially cause an application to unexpectedly halt. (Bug #69194, Bug #18641963, Bug #26474373)