19.02.1

This release is finally reproducible on Linux and MacOS!

The new aboot firmware included in this release fixes a longstanding bug (FP#26) that made impossible to power on the device while it's charging. @chrmhoffmann played a key part on this, providing Fairphone with a fix. Thanks!
Also, fastboot mode now turns on the LED blue now, which comes quite handy.

@Ingo-FP-Angel did the update to the FP OS 19.02.1 release in #14 and fixed #13 in the way. Thanks!
@z3ntu finished the MacOS compatibility in #9 and together we worked hard on getting the flashable ZIP to be deterministic again, fixing #4. Thanks!