Fix namespace usage in MySQLLoader.cpp
Merge remote-tracking branch 'upstream/master' into fix/mysqlloader
Merge pull request #166 from kateyy/fix/mysqlloader

Fix namespace usage in MySQLLoader.cpp
Add gprof-based operator-scoped profiling
Synchronize _txData structure
Remove ScopedLock
Add transaction control mechanisms for query plans

* Add automatic session pickup from request
* Add ability to automatically commit a query plan
* Clean up transaction manager interface
* Add diagnostic route /status/tx for running transactions
* Add tests
* Add exemplary python client
* Add documentation