Managing Proxyed gateways

Simple Proxying

Using the via arg of specs we can create a gateway whose io os created on a remote gateway and proxyed to the master.

The simlest use case, is where one creates one master process and uses it to controll new slaves and their environment

>>> import execnet
>>> group = execnet.Group()
>>> group.defaultspec = 'popen//via=master'
>>> master = group.makegateway('popen//id=master')
>>> master
<Gateway id='master' receive-live, thread model, 0 active channels>
>>> slave = group.makegateway()
>>> slave
<Gateway id='gw0' receive-live, thread model, 0 active channels>
>>> group
<Group ['master', 'gw0']>