* Modernize font creation
* Automate the build process, instead of writing a complicated manual
* Update sources used by the docker image away from google code
* Exclude MathJax-dev checkout from docker image, to allow image reuse
* Try to keep the individual image layers small by combining RUN commands
and removing temporary files used only during each individual step
* Allow creating fonts from local directory
Also use hash of Dockerfile to compute image tag, in order to ensure
creation of a new image if the Dockerfile changes.
* make glob syntax work on MacOS
