Accelerometer is now used to quit pinches automatically

- CWPinchManager now receives accelerometer updates. If the accelerometer values are too high, pinches are quitted. This helps us to detect if the device is moved without being tilted, which should lead to a quitPinch
- CWEventManager.trigger() can now receive an integer as the first parameter which will be used as the required log priority when logging the event messages. This can be used to not/rarely log messages of often-called event. For now, this is used for the gyroscope update messages, which appear twice every second and therefore spam our logs.
- Minor changes