add a section on snapshot releases

site/troubleshooting.md

@@ -166,3 +166,17 @@ For a more permanent solution,
 [disable Docker's auto-restart feature](https://docs.docker.com/articles/host_integration/)
 and create appropriate startup scripts to launch weave and run
 application containers from your favourite process manager.
+
+### Snapshot Releases
+
+We sometimes publish snapshot releases, to provide previews of new
+features, assist in validation of bug fixes, etc. One can install the
+latest snapshot release with
+
+    sudo wget -O /usr/local/bin/weave \
+      https://raw.githubusercontent.com/weaveworks/weave/master/weave
+    sudo chmod a+x /usr/local/bin/weave
+    sudo weave setup
+
+Snapshot releases report the script version as "(unreleased version)",
+and the container image versions as git hashes.