several fix of minor warnings

eo/src/utils/eoFDCStat.h

@@ -134,7 +134,7 @@ public:
 
   /** just to be sure the add method is not called further
    */
-  virtual void add(const eoParam& _param)
+  virtual void add(const eoParam& )
     { throw std::runtime_error("eoFDCFileSnapshot::add(). Trying to add stats to an eoFDCFileSnapshot"); }
 
 private:

eo/src/utils/eoTimedMonitor.h

@@ -72,6 +72,8 @@ public:
         return *this;
     }
 
+    using eoMonitor::add;
+
     void add(eoMonitor& mon) { monitors.push_back(&mon); }
 
   virtual std::string className(void) const { return "eoTimedMonitor"; }