Store loggers in shared pointers references #501 #537

adds related changelog entry and fix one overzealous find and replace
operation.

changelog.md

@@ -6,6 +6,10 @@ HEAD
 - Compatibility: Make sure the chrono library used by Boost/Asio is in sync
   with what the websocketpp is using. Thank you Flow86 for reporting and a
   patch.
+- Bug: Store loggers in shared pointers to avoid crashes related to connections
+  trying to write logs entries after their respective endpoint has been
+  deallocated. Thank you Thalhammer for reporting and Jupp Müller for the 
+  patch. #539 #501
 
 0.7.0 - 2016-02-22
 - MINOR BREAKING SOCKET POLICY CHANGE: Asio transport socket policy method 

websocketpp/transport/asio/connection.hpp

@@ -1120,7 +1120,7 @@ protected:
                     // TLS short read at this point is somewhat expected if both
                     // sides try and end the connection at the same time or if
                     // SSLv2 is being used. In general there is nothing that can
-                    // be done here other than a low level development log->
+                    // be done here other than a low level development log.
                 } else {
                     // all other errors are effectively pass through errors of
                     // some sort so print some detail on the info channel for