Update version to 1.8.0-SNAPSHOT

Change-Id: I6552ec90cab4de52a88b1d3df7170ec6f3623140
Reviewed-on: http://gerrit.cloudera.org:8080/9628
Reviewed-by: Todd Lipcon <todd@apache.org>
Tested-by: Todd Lipcon <todd@apache.org>
12 files changed