agent: Add telemetry messenger interface

The telemetry classes have too many responsibilities. At the moment, one
such responsibility is to send themselves to the island. As our plugin
interfaces develop, the need may arise to send telemetry using different
mechanisms. To isolate the RansomwarePayload from these changes, the
ITelemetryMessenger interface is introduced in this commit. It provides
a send_telemetry() method that handles the specific details of how
telemetry is sent to the Island.

At the present time, the TelemetryMessengerWrapper class is introduced
to handle sending telemetry. It simply wraps the existing send() method
on the telemetry class.

monkey/infection_monkey/telemetry/messengers/i_telemetry_messenger.py

@@ -0,0 +1,9 @@
+import abc
+
+from infection_monkey.telemetry.base_telem import BaseTelem
+
+
+class ITelemetryMessenger(metaclass=abc.ABCMeta):
+    @abc.abstractmethod
+    def send_telemetry(self, telemetry: BaseTelem):
+        pass

monkey/infection_monkey/telemetry/messengers/telemetry_messenger_wrapper.py

@@ -0,0 +1,7 @@
+from infection_monkey.telemetry.base_telem import BaseTelem
+from infection_monkey.telemetry.messengers.i_telemetry_messenger import ITelemetryMessenger
+
+
+class TelemetryMessengerWrapper(ITelemetryMessenger):
+    def send_telemetry(self, telemetry: BaseTelem):
+        telemetry.send()