Reproduce briar-headless.jar

See merge request !4

Install NDK to strip native libraries

See merge request !6

Install binutils-multiarch to strip native libraries

See merge request !5

Upgrade to Debian 10 to get Debian's diffoscope and apktool packages

See merge request !3

Make deterministic filesystem non-deterministic

See merge request !2

Accept new SDK License

See merge request !1

This is helpful when the script changes in a way that it can't reproduce
past releases anymore (see previous commit).

Thanks @goapunk for the prototype and the heavy lifting! :)

if the image is missing

to prevent CI failures when a new stable comes out