Subsurface-mobile Bluetooth download

[Dirk Hohndel]

After a few false starts I just did my first successful download from a
Shearwater Petrel (old model with BT only, no BLE) to a Pixel XL running
stock Android 7.1.

http://subsurface-divelog.org/downloads/test/Subsurface-mobile-4.6.4.148-arm.apk

For me it often takes several tries before Subsurface-mobile sees the dive
computer. Check in Developer->App Log. It will show you something like

Found new device Petrel (00:13:xx:xx:xx:xx)
this could be a Sheawater Petrel

(it should say something similar for other BT computer that it detects - I
tried to make it detect OSTC computer and would love if people could
verify that)

Then you go to Manage dives->Download from DC

The code to auto-populate the drop downs is broken (but I know how to fix
that), so manually set your dive computer and enable Bluetooth. Then tap
on Download and be very patient (yes, we desperately need a progress
indicator... on my list). On my Shearwater Petrel it took about 13 minutes
to download 121 dives.

Lots more work to be done - but I am ridiculously excited about this.

Thanks to Tomaz for doing all the hard work for the UI. Thanks to Jan for
helping me figure out the magic incantation (and the magic UUID) to make
this work.

Please test. Please tell me it works for other people and other dive
computers as well :-)

/D