improve docker setup

[TimoGlastra]

docker setup now allows to run tests in the docker files. It also makes use of a base indy-nodejs image to reduce build times

to test (from README):

# This build the docker image with all dependencies installed
docker build -t aries-framework-javascript .

# Run tests without network
docker run -it --rm aries-framework-javascript  yarn test -t "agents"

# Run test with network and agencies
docker-compose up # Run alice-agency and bob-agency
docker run -it --rm --network host aries-framework-javascript yarn test

Signed-off-by: Timo Glastra timo@animo.id

[jakubkoci]

Good improvements 👍

[TimoGlastra]

@jakubkoci see changes