make openafs 1.6.3

update version strings for 1.6.3, finalize release notes

Change-Id: I2f3e3dee0b1ea9e2fce522ad72e9018825b4103b
Reviewed-on: http://gerrit.openafs.org/9976
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>