Revert "[maven-release-plugin] prepare for next development iteration"

This reverts commit 1f785d46e4e3df716dc836e38933dc0a30028496.
Revert "[maven-release-plugin] prepare release v0.9.1-rc2"

This reverts commit 1197280acf1322165301259dd825f44e22a323bc.
Updated CHANGES.txt
[maven-release-plugin] prepare release v0.9.1-rc3
[maven-release-plugin] prepare for next development iteration