[gekko 0.6] API change for running a backtest

[thegamecat]

Regarding db and speed...I'm generally of the belief that while sqlite is great for using out of the box Gekko, postgres is the way forward generally - and some will swear by Mongo. So any speed benefits in this context should be:

1) Gekko core
2) Some community guides on how to increase performance on the db itself - maybe with some tweaks to the db plugins.