Add support for callbacks in the Schedd.query method.
Allow DC sockets to be registered for write.
Allow CEDAR to indicate when there is a backlog for sending packets to the network.  Use this to implement a putClassAd variant which can detect backlog.
WARNING.  This breaks the condor_q wire protocol to allow streaming of ClassAds.
Debug non-blocking mode of ReliSock. #0

Start to make condor_q responses non-blocking.
Merge branch 'non_blocking_condor_q' of github.com:bbockelm/htcondor
into non_blocking_condor_q. #0

Conflicts:
	src/condor_utils/classad_oldnew.h