Create Dockerfile for Drupalizer with a custom entrypoint

The contents of the Dockerfile are based on the same file in boilerplate
meta-repository that is normally used in combination with Drupalizer.

Dockerfile

+# docker Drupal
+# VERSION       0.3
+FROM    savoirfairelinux/lampd
+MAINTAINER Ernesto Rodriguez Ortiz <ernesto.rodriguezortiz@savoirfairelinuc.com>
+
+# Create entrypoint script
+RUN mkdir -p /opt/init
+RUN echo '#!/bin/bash\n\
+\n\
+exec /bin/sh -c "$*"'\
+> /opt/init/init.sh && chmod a+x /opt/init/init.sh
+
+# Create project root directory and copy the structure
+RUN mkdir -p /opt/sfl
+COPY . /opt/sfl
+
+# Setup ssh keys to clone git repo
+RUN mv /opt/sfl/conf/id_rsa* /root/.ssh/
+RUN cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys
+RUN chmod 600 /root/.ssh/id_rsa*
+RUN exec ssh-agent /bin/bash && ssh-add /root/.ssh/id_rsa
+RUN ssh-keyscan gitlab.savoirfairelinux.com >> /root/.ssh/known_hosts
+
+#Copy vhost configuration and enable modules
+RUN cp /opt/sfl/conf/vhost.conf /etc/apache2/sites-available/000-default.conf
+RUN a2enmod rewrite vhost_alias
+
+ENTRYPOINT ["/opt/init/init.sh"]
+CMD ["/sbin/my_init"]