Remove unused is_up_to_date network method

lib/network.py

@@ -315,9 +315,6 @@ class Network(util.DaemonThread):
     def is_connecting(self):
         return self.connection_status == 'connecting'
 
-    def is_up_to_date(self):
-        return self.unanswered_requests == {}
-
     @with_interface_lock
     def queue_request(self, method, params, interface=None):
         # If you want to queue a request on any interface it must go

lib/wallet.py

@@ -218,10 +218,7 @@ class Abstract_Wallet(PrintError):
         self.load_unverified_transactions()
         self.remove_local_transactions_we_dont_have()
 
-        # There is a difference between wallet.up_to_date and network.is_up_to_date().
+        # wallet.up_to_date is true when the wallet is synchronized
-        # network.is_up_to_date() returns true when all requests have been answered and processed
-        # wallet.up_to_date is true when the wallet is synchronized (stronger requirement)
-        # Neither of them considers the verifier.
         self.up_to_date = False
 
         # save wallet type the first time