lock the yum repo down as well

Dockerfile

@@ -1,20 +1,21 @@
 FROM amazonlinux:2017.03.1.20170812
 MAINTAINER Levi Wilson <[email protected]>
 
+# lock yum to the same repository version
+RUN sed -i 's/releasever=.*/releasever=2017.03/g' /etc/yum.conf
+
+# base requirements
 RUN yum install yum-utils zip -y && \
     yum-config-manager --enable epel && \
-    yum update -y && \
-    yum install git libpng-devel libcurl-devel gcc python-devel libjpeg-devel -y
-
-RUN yum install python27 python27-setuptools.noarch -y
+    yum install git libpng-devel libcurl-devel gcc python27-devel libjpeg-devel -y
 
+# pip
 RUN alias sudo='env PATH=$PATH' && \
     curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && \
     python get-pip.py && rm get-pip.py && \
     pip install --upgrade setuptools && \
     pip install --upgrade virtualenv
 
 # pycurl
-RUN yum install -y gcc-c++ make python27-devel openssl-devel
-
+RUN yum install -y openssl-devel
 ENV PYCURL_SSL_LIBRARY=openssl