Automate HassIO builds using Gitlab CI (#52)

* Add Gitlab CI

* Fix aarch64 edge build

docker/Dockerfile.builder

@@ -0,0 +1,32 @@
+FROM multiarch/ubuntu-core:amd64-xenial
+
+# setup locals
+RUN apt-get update && apt-get install -y \
+        jq \
+        git \
+        python3-setuptools \
+    && rm -rf /var/lib/apt/lists/* \
+ENV LANG C.UTF-8
+
+# Install docker
+# https://docs.docker.com/engine/installation/linux/docker-ce/ubuntu/
+RUN apt-get update && apt-get install -y \
+        apt-transport-https \
+        ca-certificates \
+        curl \
+        software-properties-common \
+    && rm -rf /var/lib/apt/lists/* \
+    && curl -fsSL https://download.docker.com/linux/ubuntu/gpg | apt-key add - \
+    && add-apt-repository "deb https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" \
+    && apt-get update && apt-get install -y docker-ce \
+    && rm -rf /var/lib/apt/lists/*
+
+# setup arm binary support
+RUN apt-get update && apt-get install -y \
+        qemu-user-static \
+        binfmt-support \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY hassio-builder.sh /usr/bin/
+
+WORKDIR /data