Use Circle CI for faster builds. (#181)

Move to Circle CI from Travis CI.

.travis/deploy.sh

@@ -0,0 +1,17 @@
+#! /bin/bash
+
+deploy() {
+	REG_URL=${REGISTRY}_URL
+	REG_USER=${REGISTRY}_USER
+	REG_PASS=${REGISTRY}_PASS
+	docker login -u ${!REG_USER} -p ${!REG_PASS} ${!REG_URL}
+	docker push ${!REG_URL}/maxking/mailman-web:$1
+	docker push ${!REG_URL}/maxking/mailman-core:$1
+}
+
+if [ ! "$BRANCH" = "master" ] && [ "$PULL_REQUEST" ]; then
+	echo "Deploy only from master branch. This is $TRAVIS_BRANCH"
+	exit 0
+fi
+
+deploy