Update the Dockerfile according to best practices

see
https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/

Dockerfile

@@ -1,33 +1,29 @@
 FROM debian:jessie
 
-MAINTAINER Liblouis Maintainers "[email protected]"
-
-# developer environment
-RUN apt-get update
-RUN apt-get install -y make autoconf automake libtool pkg-config
-
-# for python bindings
-RUN apt-get install -y python
-
-# for documentation
-RUN apt-get install -y texinfo
-
-# for tests
-RUN apt-get install -y libyaml-dev
+LABEL maintainer="Liblouis Maintainers <[email protected]>"
+
+# Fetch build dependencies
+RUN apt-get update && apt-get install -y \
+    autoconf \
+    automake \
+    curl \
+    libtool \
+    libyaml-dev \
+    make \
+    pkg-config \
+    python \
+    texinfo \
+   && rm -rf /var/lib/apt/lists/*
 
 # compile and install liblouis
-ADD . /tmp/liblouis
-WORKDIR /tmp/liblouis
-RUN ./autogen.sh
-RUN ./configure --enable-ucs4
-RUN make
-RUN make install
-RUN ldconfig
+ADD . /usr/src/liblouis
+WORKDIR /usr/src/liblouis
+RUN ./autogen.sh && ./configure --enable-ucs4 && make && make install && ldconfig
 
 # install python bindings
-WORKDIR /tmp/liblouis/python
+WORKDIR /usr/src/liblouis/python
 RUN python setup.py install
 
 # clean up
 WORKDIR /root
-RUN rm -rf /tmp/liblouis
+RUN rm -rf /usr/src/liblouis