Adds both build and push support

This adds support for building and pushing docker containers
when you perform either `kompose convert` or `kompose up`.

Docker Compose files who have build parameters with their respective
image and build keys will automatically be both built and pushed.

script/test/fixtures/buildconfig/build/Dockerfile

@@ -0,0 +1,2 @@
+FROM busybox
+RUN touch /test

script/test/fixtures/buildconfig/docker-compose-build-no-image.yml

@@ -0,0 +1,5 @@
+version: "2"
+
+services:
+    foo:
+        build: "./build"

script/test/fixtures/buildconfig/docker-compose.yml

@@ -0,0 +1,6 @@
+version: "2"
+
+services:
+    foo:
+        build: "./build"
+        image: docker.io/cdrage/foobar