build-for-arm.md

How to build duniter-v2s for arm

1. Create a docker image that contains the build environment

docker build -t duniter-v2s-arm-builder -f docker/cross-arm.Dockerfile .

2. Use this docker image to cross-compile duniter-v2s for armv7

./scripts/cross-build-arm.sh

then, get the final binary at target/armv7-unknown-linux-gnueabihf/release/duniter.