make 1.6.3pre2

prerelease for OpenAFS 1.6.3

Change-Id: Ie6148239feae53bdaca9409c6b75714a25968c00
Reviewed-on: http://gerrit.openafs.org/9909
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>