Windows: Monitor requests and gather diagnostics before a timeout

Windows: Monitor requests and gather diagnostics before a timeout

This patch monitors SMB requests that are being serviced and
automatically enables logging if a request takes longer than one
minute to complete.  If the requst hasn't completed by the two minute
mark, the code generates a minidump.  Once a minimump is generated, no
more minidumps will be produced for another 5 minutes.

SMB monitoring can be enabled/disabled using the new registry
parameter 'SMBRequestMonitor.'

Change-Id: I5aae22f6bfa635cec4a803089b483698641080eb
Reviewed-on: http://gerrit.openafs.org/1632
Reviewed-by: Asanka Herath <asanka@secure-endpoints.com>
Tested-by: Asanka Herath <asanka@secure-endpoints.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Tested-by: Jeffrey Altman <jaltman@openafs.org>