Remove date from container_version in preparation for release

Author: dhalperi

pom.xml

@@ -80,7 +80,7 @@
     <beam.version>0.4.0</beam.version>
 
     <dataflow.release_name>Google Cloud Dataflow SDK for Java</dataflow.release_name>
-    <dataflow.container_version>${project.version}-20170103</dataflow.container_version>
+    <dataflow.container_version>${project.version}</dataflow.container_version>
     <dataflow.environment_major_version>6</dataflow.environment_major_version>
   </properties>