Adding makefile target to build the tool only

[tjyang]

Hi @hupe1980

I am hoping to use docker container as an isolated golang compiling environment, not doing the scan tests inside container.
Can you add a target to automate this goal using following example I found on internet ?
like "make docker-compile"

docker create -ti --name dummy IMAGE_NAME bash
docker cp dummy:/path/to/file /dest/to/file  # copy scan4log4shell out to local partition like /tmp.
docker rm -f dummy

[hupe1980]

You can now find Docker support in the readme