Version 0.1.9 update Mai's route

Version 0.1.9 update:

1. Progress on Mai's route
2. Added a convenience store scene in Mai's route, featuring Yuanyuan and the cashier (but the cashier's scenes will be released later)
3. Freya's second day office scene completed

Version 0.1.9.1 will be released this Sunday.
I am still finishing up some scenes.