First attempt at an implementation of a non-blocking shared port client.
Fix handling of NULL char *; fix non-blocking logic. #4094
Mark socket as non-blocking when a connection attempt is made. #4094

This causes clients to be rejected as soon as the daemon's backlog
is hit.  This is equivalent behavior to the case where the daemon
is listening on the network and the TCP socket backlogs.
ifdef out portions which will not compile under Windows. #4094
Merge branch 'master' into shared_port_nonblocking
Merge branch 'master' into shared_port_nonblocking
Merge branch 'master' into shared_port_nonblocking
Merge remote-tracking branch 'github/shared_port_nonblocking' into shared_port_nonblocking
Attempt to make the shared port transparently forward collector connections.
Allow shared port to peacefully coexist with the collector. #0
Have COLLECTOR_USES_SHARED_PORT do the requisite configuration. #3813
Merge branch 'master' into default_shared_port. #3813

Merge was done by hand and tested to the point where it compiles
and the logic looks right.  Needs testing.

Conflicts:
	src/condor_daemon_core.V6/condor_daemon_core.h
	src/condor_daemon_core.V6/daemon_command.cpp
	src/condor_daemon_core.V6/daemon_core.cpp
	src/condor_io/shared_port_client.cpp
	src/condor_io/shared_port_client.h
	src/condor_io/shared_port_server.cpp
	src/condor_utils/param_info.in
Cleanups from testing branch. #3813

- Actually turn on USE_SHARED_PORT by default as the branch suggests.
- Fix bug on IPv6 socket binding caused by default arguments to bind.
- Avoid binding the UDP socket twice.
Merge branch 'master' into default_shared_port
Move the state checking to the dag nodes as there can be a lag
before they may see the real state. Have the nodes be patient
about what they expect to see. #3594
Merge branch 'V8_2-branch' into V8_3_0-branch
Merge branch 'V8_3_0-branch'
Documentation and changes from code review.  #3813
Enforce Globus thread model "none". #4464

If the Globus thread model is not "none", then Globus will use
lt_dlopen() to load a Globus library with routines for the given thread
library. This is likely to fail for UW builds of Condor, as lt_dlopen()
ignores the RPATH, which is how we locate the Globus libraries we ship
with Condor.
The thread model can be set via GLOBUS_THREAD_MODEL in the environment.
Override that with an explicit call to globus_thread_set_model().
Fix how arguments are passed to remote_gahp by the gridmanager. #4434

Now, for grid batch jobs that want to use remote_gahp, the options
included in the GridResource attribute are placed before the name of the
remote gahp binary in the argument list for remote_gahp.
These options are meant for remote_gahp, so this makes more sense than
the previous ordering.