Fix live code upgrades by jumping out of receive in loops

Jump out of receive in loops after 5s to enable live code upgrades.

Author: weisslj

src/mysql_conn.erl

@@ -413,6 +413,8 @@ loop(State) ->
 	    ?Log2(LogFun, error,
 		  "received unknown signal, exiting: ~p", [Unknown]),
 	    error
+    after 5000 ->
+	    loop(State)
     end.
 
 %% GenSrvFrom is either a gen_server:call/3 From term(),

src/mysql_recv.erl

@@ -146,6 +146,8 @@ loop(State) ->
 		   end),
 	    State#state.parent ! {mysql_recv, self(), closed, normal},
 	    error
+    after 5000 ->
+	    loop(State)
     end.
 
 %%--------------------------------------------------------------------