compile fixes

include/connection.h

@@ -74,7 +74,7 @@ public:
      */
     const std::string &vhost() const
     {
-        return _implemention.vhost();
+        return _implementation.vhost();
     }
 
     /**

include/login.h

@@ -81,7 +81,7 @@ public:
      *  String representation in SASL PLAIN mode
      *  @return string
      */
-    std::string saslPlain()
+    std::string saslPlain() const
     {
         // we need an initial string
         std::string result("\0", 1);