Add files for Paxos decision system.

DecisionSystem/PaxosDecision/paxosmessenger.py

@@ -0,0 +1,37 @@
+from proposal import Proposal
+
+class Messenger():
+    def send_prepare(self, proposal_id):
+        '''
+        Broadcasts a Prepare message to all Acceptors
+        '''
+
+        NotImplementedError
+
+    def send_promise(self, proposer_id, proposal_id, previous_proposal):
+        '''
+        Sends a Promise message to the specified Proposer
+        '''
+
+        NotImplementedError
+
+    def send_accept(self, proposal):
+        '''
+        Broadcasts an Accept message to all Acceptors
+        '''
+
+        NotImplementedError
+
+    def send_accepted(self, proposal):
+        '''
+        Broadcasts an Accepted message to all Learners
+        '''
+
+        NotImplementedError
+
+    def on_resolution(self, proposal_id, value):
+        '''
+        Called when a resolution is reached
+        '''
+
+        NotImplementedError