Fix plugins except log in plugin install

cloudcontrol/node/host/plugins.py

@@ -38,8 +38,9 @@ class Plugin(object):
         module.on = self._decorator_event
         try:
             exec plugin_body in module.__dict__
-        except Exception:
-            err_msg = 'Error during plugin installation (%s)' % self.name
+        except Exception as exc:
+            err_msg = 'Error during plugin installation (%s): %s' % (
+                self.name, exc)
             logger.exception(err_msg)
             raise RuntimeError(err_msg)
         else: