Update dxWDL version in Dockerfile (#177)
Update dxWDL version in Dockerfile (#177)

* Update dxWDL version
* use build arg instead
* Fix up entrypoint

Let's you do `docker run <image> compile`, etc because then it appends arguments to command

dnanexus-rnd/dxWDL,dnanexus-rnd/dxWDL