Add the xenstore ring analyser

Signed-off-by: David Scott <dave.scott@citrix.com>
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@citrix.com>
Make the packet parser more robust to truncated packets

Signed-off-by: David Scott <dave.scott@citrix.com>
Update CHANGES

Signed-off-by: David Scott <dave.scott@citrix.com>
dbgring: ignore blocks of 0s

These are more likely to be unused space than explicit "Debug"
packets.

Signed-off-by: David Scott <dave.scott@citrix.com>
Merge pull request #42 from djs55/dbgring

Import ring diagnostics tool