Proper up internal factoring/interfaces for IDealer/IBroker

[oberstet]

oberstet@intel-nuci7:~$ find scm/crossbario/crossbar/crossbar -name "*.py" -exec grep -Hi IDealer {} \;
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.attach`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.detach`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processRegister`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processUnregister`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processCall`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processCancel`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processYield`
scm/crossbario/crossbar/crossbar/router/dealer.py:        Implements :func:`crossbar.router.interfaces.IDealer.processInvocationError`
oberstet@intel-nuci7:~$ find scm/crossbario/crossbar/crossbar -name "*.py" -exec grep -Hi IBroker {} \;
scm/crossbario/crossbar/crossbar/router/broker.py:        Implements :func:`crossbar.router.interfaces.IBroker.attach`
scm/crossbario/crossbar/crossbar/router/broker.py:        Implements :func:`crossbar.router.interfaces.IBroker.detach`
scm/crossbario/crossbar/crossbar/router/broker.py:        Implements :func:`crossbar.router.interfaces.IBroker.processPublish`
scm/crossbario/crossbar/crossbar/router/broker.py:        Implements :func:`crossbar.router.interfaces.IBroker.processSubscribe`
scm/crossbario/crossbar/crossbar/router/broker.py:        Implements :func:`crossbar.router.interfaces.IBroker.processUnsubscribe`
oberstet@intel-nuci7:~$ cloc scm/crossbario/crossbar/crossbar/interfaces.py 
       1 text file.
       1 unique file.                              
       0 files ignored.

github.com/AlDanial/cloc v 1.90  T=0.01 s (95.9 files/s, 33179.3 lines/s)
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oberstet@intel-nuci7:~$