bozo: bosserver -pidfiles option

bozo: bosserver -pidfiles option

Add an option to bosserver to create pidfiles for long running
processes for simple, fs, and dafs bnode types, as well as the
bosserver process. The pidfiles are located in the server local
directory by default, or in the path specifed by the -pidfiles
command-line option.

Reviewed-on: http://gerrit.openafs.org/5497
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit bdf86d245fd55c5c7ac7ea81e3d6b6bafdbe1783)

Change-Id: Id76530b81e2e92c76a015510d04dc8d5e5fd75ce
Reviewed-on: http://gerrit.openafs.org/5537
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementix.org>