v3.1.0 release

Dockerfile

@@ -1,6 +1,6 @@
 FROM alpine:3.1
 
 RUN apk --update add python py-pip && \
-    pip install elasticsearch-curator==3.0.3
+    pip install elasticsearch-curator==3.1.0
 
 ENTRYPOINT ["/usr/bin/curator"]

README.md

@@ -14,7 +14,7 @@ resulting in just 50mb image.
 Image entrypoint is set to curator script, so just run the image:
 
 ```
-docker run --rm bobrik/curator:3.0.3 --help
+docker run --rm bobrik/curator:3.1.0 --help
 ```
 
 Pick whatever version you need.