TODO before 0.12.0 release:

* ~~Patch GreenDAO to support composite primary keys~~
* ~~Support importing Pebble Health data from old database~~ DONE, needs check.
* Fix user attribute table being spammed
* Add onboarding activity on first startup (to merge old data)

Non blocking issues:

* Add back UUID_CHARACTERISTIC_PAIR support, at least optionally
* CSV Export
* Imorove mapping from device to device coordinator + support class