libcutils: qtaguid: Support new functions, add tag resource tracking.

* Add support for
  deleteTagData(tag, uid)
  setCounterSet(counterSetNum, uid)
  setPacifier(on)

* Add resource tracking
(If only kernel process termination had a hook)
Because the xt_qtaguid netfilter module needs to keep track of
tagged sockets, it needs a way to know when the process owning
the socket has died.
Normally the app will untag the sockets. But not on crash.
So the process opens the qtaguid misc dev, which is closed on crash,
at which point the xt_qtaguid can force-untag the processes sockets,
and thus allowing their refcount to go down and release them.

* Add pacifier support
 Add function to enable/disable pacification of the xt_qtaguid
 kernel module. (mostly for debugging)

Change-Id: I7f2228e65208046dd37ec1c7407ee307d5ba9b99