Changed dockerfile base image to debian.

If the comment https://github.com/docker/docker/issues/783#issuecomment-55537066
is right, the issue being discussed there will stop here.
Interesting is that it start happening only with the Docker-autobuild image;
when I do it on my local machine, I have no problems with the instances.

dockerfile/Dockerfile

-FROM ubuntu:trusty
+FROM debian:jessie
 
 LABEL Description=DaCHS\ is\ a\ publishing\ infrastructure\ for\ the\ Virtual\ Observatory. \
       Author=Markus\ Demleitner \
@@ -7,26 +7,34 @@ LABEL Description=DaCHS\ is\ a\ publishing\ infrastructure\ for\ the\ Virtual\ O
 
 MAINTAINER "Carlos Brandt <carloshenriquebrandt at gmail>"
 
-ENV LANG en_US.UTF-8
-ENV LANGUAGE en_US:en
-ENV LC_CTYPE C.UTF-8
-
-RUN locale-gen --purge $LANG && \
-    echo LANG="$LANG" > /etc/default/locale && \
-    echo LANGUAGE="$LANGUAGE" >> /etc/default/locale && \
-    echo LC_CTYPE="$LC_CTYPE" >> /etc/default/locale
-
 ENV DEBIAN_FRONTEND noninteractive
 
 RUN apt-get update && \
-    apt-get install -y sudo wget vim && \
+    apt-get install -y sudo wget vim locales && \
     apt-get clean
 
+# This is the brute-force solution for Debian;
+# I am having problems in set locales non-interactively,
+# and since I really need the "C/UTF8" for postgres, will just set it for all.
+ENV LC_ALL C.UTF-8
+RUN echo LC_ALL="$LC_ALL" > /etc/default/locale
+
+# I'll leave the lines below for further look;
+# These work just find under Ubuntu.
+# (Yeah, I'll remove these lines in the near future...probably...)
+#ENV LANG en_US.UTF-8
+#ENV LANGUAGE en_US:en
+#ENV LC_CTYPE C.UTF-8
+#RUN locale-gen --purge $LANG && \
+#    echo LANG="$LANG" > /etc/default/locale && \
+#    echo LANGUAGE="$LANGUAGE" >> /etc/default/locale && \
+#    echo LC_CTYPE="$LC_CTYPE" >> /etc/default/locale
+
 RUN echo 'deb http://vo.ari.uni-heidelberg.de/debian stable main' > /etc/apt/sources.list.d/gavo.list && \
     echo 'deb-src http://vo.ari.uni-heidelberg.de/debian stable main' >> /etc/apt/sources.list.d/gavo.list && \
     wget -qO - http://docs.g-vo.org/archive-key.asc | apt-key add -
 
-RUN echo 'deb http://apt.postgresql.org/pub/repos/apt/ trusty-pgdg main' > /etc/apt/sources.list.d/pgdg.list && \
+RUN echo 'deb http://apt.postgresql.org/pub/repos/apt/ jessie-pgdg main' > /etc/apt/sources.list.d/pgdg.list && \
     wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | apt-key add -
 
 RUN sed -i 's/exit 101/exit 0/' /usr/sbin/policy-rc.d