Protocol muxing (#82)

* Implement protocol muxing

* Integrate protocol muxing into new stream and listen's conn handler

* Fix bugs in protocol muxing

* Remove blank line

* Add comments and fix linting issues

* Fix order of parameters to select_one_of to match interface

* Use array of protocol ids in new stream instead of protocol id

* Add basic protocol muxer tests

* Add todo

* Modify new stream to take in protocol ids

* Add check to all tests to ensure protocol id is saved to net stream properly

* Lint tests

* Fix lint issues

* Add todo

* Modify port numbers in tests

* Fix linting issues

* Add more documentation to functions

* Add docs describing classes and fix indent error

protocol_muxer/multiselect_communicator_interface.py

@@ -0,0 +1,21 @@
+from abc import ABC, abstractmethod
+
+class IMultiselectCommunicator(ABC):
+    """
+    Communicator helper class that ensures both the client
+    and multistream module will follow the same multistream protocol,
+    which is necessary for them to work
+    """
+
+    @abstractmethod
+    def write(self, msg_str):
+        """
+        Write message to stream
+        :param msg_str: message to write
+        """
+
+    @abstractmethod
+    def read_stream_until_eof(self):
+        """
+        Reads message from stream until EOF
+        """