Change connection priority

[aanders77]

Is your feature request related to a problem? Please describe. We're going to send firmware updates to a BLE device, and want the transfer to take as little time as possible.

Describe the solution you'd like It would be nice to be able to change connection priority https://developer.android.com/reference/android/bluetooth/BluetoothGatt#requestConnectionPriority(int)

Also, being able to request a bigger MTU size might help to increase transfer speed. https://developer.android.com/reference/android/bluetooth/BluetoothGatt#requestMtu(int)

Describe alternatives you've considered The device manufacturer sent us a java-based example application where they used the two mentioned methods to increase transfer speeds. But the firmware is less than 1MB, so tbh I haven't got a chance yet to test if there is a noticable difference.