Add buildargs and import examples.

Author: shanejbrown

examples/build/buildargs/buildrunner.yaml

@@ -0,0 +1,18 @@
+# This example demonstrates how to use the buildargs field in the build step.
+# The buildargs field allows you to pass build-time variables to the Dockerfile.
+steps:
+  buildargs-step:
+    build:
+      buildargs:
+        MY_VERSION: 2.0
+      dockerfile: |
+        FROM alpine:latest
+        ARG MY_VERSION
+        LABEL version=$MY_VERSION
+
+    # To view the label in the built image do the following:
+    #  1. Uncomment the following 'push:' line
+    #  2. Run 'PYTHONPATH=. ./bin/buildrunner -f examples/build/buildargs/buildrunner.yaml'
+    #  3. Run 'docker image inspect my-images/buildargs-image:latest' to see the label.
+    #
+    # push: my-images/buildargs-image:latest

examples/build/import/buildrunner.yaml

@@ -0,0 +1,11 @@
+# This example demonstrates how to import a tarball image in the build step.
+# This requires the tarball image to be present in the same directory where buildrunnner is executed.
+# Before running this example, make sure to create a tarball image using the following command:
+# docker save alpine:latest -o alpine.tar
+#
+# WARNING: Do not commit the tarball image to the repository.
+#
+steps:
+  import-step:
+    build:
+      import: alpine.tar

run-buildrunner.sh

@@ -3,4 +3,4 @@
 # This script will run the local buildrunner code from the root of the project
 # ./run-buildrunner.sh --help
 # ./run-buildrunner.sh -f examples/build/basic/buildrunner.yaml
-PYTHONPATH=. ./bin/buildrunner "$@"
+PYTHONPATH=. ./bin/buildrunner --cleanup-images "$@"