Update script

Author: gustavocmaciel

doc/source/development/contributing.rst

@@ -163,7 +163,7 @@ with a full pandas development environment.
 
 There is a script to help you with this::
 
-    ./docker.sh
+    ./scripts/docker.sh
 
 When prompted, enter your Github username.
 

scripts/docker.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+#
+# Set up a development environment with Docker.
+
+run_container () {
+    # Run a container and bind the local forked repo to it
+    docker run -it --rm -v "$(pwd)":/home/pandas-"$USER" pandas-"$USER"-env
+}
+
+# Check if pandas image already exists
+docker image ls | grep "pandas-$USER-env" &> /dev/null
+
+if [[ $? == 0 ]]; then
+
+    run_container
+
+else
+
+    # Pass the Github username as the build variable
+    read -rp "Github username: " gh_username
+    docker build --tag pandas-"$USER"-env --build-arg gh_username=$gh_username .
+
+    run_container
+
+fi