Merge pull request #355 from msabramo/run_docker-configurable

Allow configuring run_docker ports using env vars

run_docker

 #!/bin/sh
-DOCKER_PORT=8000
-SYSTEM_PORT=8000
 
-docker run -p $SYSTEM_PORT:$DOCKER_PORT --rm -v $PWD:/src --user root -e NB_UID=$UID -e NB_GID=$GID -it iodide/pyodide-env:0.3.1 /bin/bash
+PYODIDE_DOCKER_PORT=${PYODIDE_DOCKER_PORT:-"8000"}
+PYODIDE_SYSTEM_PORT=${PYODIDE_SYSTEM_PORT:-"8000"}
+PYODIDE_DOCKER_IMAGE=${PYODIDE_DOCKER_IMAGE:-"iodide/pyodide-env:0.3.1"}
+
+exec docker run \
+    -p $PYODIDE_SYSTEM_PORT:$PYODIDE_DOCKER_PORT \
+    -it --rm \
+    -v $PWD:/src \
+    --user root -e NB_UID=$UID -e NB_GID=$GID \
+    ${PYODIDE_DOCKER_IMAGE} \
+    /bin/bash