Set release version 5.2.0

Change-Id: I1e2944364876bed4c83d1c193046321475891373
Next development version 5.2.1-SNAPSHOT

Change-Id: I6b81e9e67e2e9c8ad449c14fc00f734262b40469
next version will be 5.3.0

Change-Id: Id6af20587a3cdad29bb6f09e4b57b79285cda842