SLING-3620 - POM preparations for release

Bump the version to 1.0.0

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1604756 13f79535-47bb-0310-9956-ffa450edef68
SLING-3620 - POM preparations for release

Force the qualifier to be 'RELEASE' in preparation for the 1.0.0 release
vote.

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1604757 13f79535-47bb-0310-9956-ffa450edef68