THRIFT-3696 Install pip to CentOS Docker images to fix Python builds

This closes #912
diff --git a/build/docker/ubuntu/Dockerfile b/build/docker/ubuntu/Dockerfile
index 44ad147..5180fca 100644
--- a/build/docker/ubuntu/Dockerfile
+++ b/build/docker/ubuntu/Dockerfile
@@ -55,15 +55,16 @@
     && update-java-alternatives -s java-1.7.0-openjdk-amd64
 
 # Python dependencies
-RUN apt-get update && apt-get install -y \
+RUN apt-get update && apt-get install -y --no-install-recommends \
       python-all \
-      python-all-dev \
       python-all-dbg \
+      python-all-dev \
+      python-pip \
       python-setuptools \
       python-support \
       python-twisted \
       python-zope.interface \
-      python-pip \
+      python3-dev \
       python3-pip
 
 # Ruby dependencies