Revert version to 2.3.0 for first release of 2.3.x branch

Signed-off-by: Byron Ruth <b@devel.io>
Update Serrano max version to 2.3.6

Signed-off-by: Byron Ruth <b@devel.io>
2.3.0 Release

Signed-off-by: Byron Ruth <b@devel.io>
2.3.1 Beta

Signed-off-by: Byron Ruth <b@devel.io>