Revert "change: removed log_base from service_provider_base"

This reverts commit 9bb222a.

Author: robert-burger

include/robotkernel/service_provider_base.h

@@ -36,6 +36,7 @@
 #include "robotkernel/device_listener.h"
 #include "robotkernel/exceptions.h"
 #include "robotkernel/helpers.h"
+#include "robotkernel/log_base.h"
 #include "robotkernel/service_interface.h"
 #include "robotkernel/robotkernel.h"
 
@@ -170,6 +171,7 @@ namespace robotkernel {
 
 template <class T, class S>
 class service_provider_base : 
+    public log_base, 
     public device_listener,
     public std::enable_shared_from_this<service_provider_base<T, S> >
 {
@@ -187,6 +189,7 @@ class service_provider_base :
          * \param name instance name
          */
         service_provider_base(const std::string& name, const std::string& impl) : 
+            log_base(name, impl, ""),
             device_listener(name, "listener")
         {};
 
@@ -277,10 +280,13 @@ inline void service_provider_base<T, S>::add_interface(std::shared_ptr<service_i
         handler = std::make_shared<T>(local_req);
     } catch (std::exception& e) {
         // if exception is thrown, req does not belong to us
+        log(warning, "adding interface: %s\n", e.what());
         handler = NULL;
     }
 
     if (handler) {
+        log(verbose, "got new service_interface: owner %s, id %s\n", 
+                local_req->owner.c_str(), local_req->id().c_str());
         handler_map[std::make_pair(local_req->owner, local_req->id())] = handler;
     }
 };