Fixed broken R container (#247)

Author: dcrankshaw

RPythonDockerfile

@@ -4,7 +4,7 @@ FROM clipper/py-rpc:latest
 RUN echo "deb http://http.debian.net/debian sid main" > /etc/apt/sources.list.d/debian-unstable.list \
 	&& echo 'APT::Default-Release "testing";' > /etc/apt/apt.conf.d/default
 
-ENV R_BASE_VERSION 3.4.0
+ENV R_BASE_VERSION 3.4
 
 ## Now install R and littler, and create a link for littler in /usr/local/bin
 ## Also set a default CRAN repo, and make sure littler knows about it too