sling-query - remove CHANGELOG.md and bump version to 2.0.0-SNAPSHOT

See discussion at http://sling-dev.markmail.org/thread/xiruzia372scxqzb#query:+page:1+mid:mzrdqgooezpz43cz+state:results


git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1616697 13f79535-47bb-0310-9956-ffa450edef68