Resolve "Add RabbitMQ for MessageBus triggers"

Closes #1 (closed)

\approve @ds @gislars

Dockerfile

@@ -6,12 +6,12 @@ RUN apt-get update \
     postgresql-contrib \
     postgresql-$PG_MAJOR-postgis-$POSTGIS_VERSION \
     postgresql-$PG_MAJOR-postgis-$POSTGIS_VERSION-scripts \
+    build-essential \
     python3-pip \
     python-dev \
     python-setuptools; \
     done \
   && apt-get clean \
   && rm -rf /var/lib/apt/lists/*
-RUN find / -name "postgres.h" -print \
-    && pip install pgxnclient \
-    && pgxnclient install pg_amqp
+RUN pip install pgxnclient
+RUN pgxnclient install pg_amqp