* saved a simplified contrib/docker/Makefile and helper scripts

* fixed flow for make targets

* restored original definition for setting the PARALLEL option on the command line per github comments

* remove double build for make install targets

* added a save for the ngraph_dist_gcc.tgz to maintain existing behavior

* fixed passing the PARALLEL value to the make targets

* integrated latest working build-ngraph-and-test script

* integrated the latest working Makefile

* removed reference to the THIRD_PARTY_CACHE_DIR (for future)

* updated the contrib/docker/README.md file