[OXT-43] xenmgr: Remove Dbus matches on VM delete

OXT-43

Add functionality to removeVm such that we invoke new functions defined in libxch-rpc
to make RemoveMatch calls to DBus.  This is a fix for xenmgr maxing out on dbus rules
during VM creation.

Signed-off-by: Chris Rogers rogersc@ainfosec.com
This patch addresses at least part of the FIXME.  I think there's more to be done to 'cleanly' stop monitoring events, but that might require someone more versed in Haskell than me.  This patch is a step in the right direction as the previous method was simply to not clean anything and let a reboot take care of it.  Another potential target for cleaning is the VmMonitor "object" since it registers and stores event handlers.