Configure mgr and mail containers

This commit configures IMAP to work properly and makes logs of mgr and
dovecot available.

mgr.Dockerfile

@@ -10,6 +10,7 @@ RUN apt-get update \
     locales-all \
     mariadb-client \
     nullmailer \
+    php5-imap \
     php5-mysql \
     zendframework \
     && apt-get clean \
@@ -33,6 +34,7 @@ VOLUME /var/www
 RUN a2ensite mgr.cacert.localhost ; \
     a2dissite 000-default ; \
     a2enmod headers ; \
+    a2enmod rewrite ; \
     a2enmod ssl ; \
     cd /usr/local/share/ca-certificates ; \
     curl -O http://www.cacert.org/certs/root_X0F.crt ; \