Improve error message on not finding a particular name.

This happened to me when one of the nodes present in the default biped guide got a new name, e.g. `arm_L0_L0_root` which caused the `getName` to return a missing name, e.g. `arm_L0_root`. The previous error message simply said "Object missing: root" whereas now it says "Object missing: arm_L0_root"; a little more descriptive.

scripts/mgear/maya/shifter/component/guide.py

@@ -263,7 +263,9 @@ def setFromHierarchy(self, root):
             else:
                 node = dag.findChild(self.model, self.getName(name))
                 if not node:
-                    mgear.log("Object missing : %s"%name, mgear.sev_warning)
+                    mgear.log("Object missing : %s" % (
+                        self.getName(name), mgear.sev_warning)
+                    )
                     self.valid = False
                     continue
 
@@ -276,7 +278,9 @@ def setFromHierarchy(self, root):
 
             node = dag.findChild(self.model, self.getName(name))
             if not node:
-                mgear.log("Object missing : %s"%name, mgear.sev_warning)
+                mgear.log("Object missing : %s" % (
+                    self.getName(name), mgear.sev_warning)
+                )
                 self.valid = False
                 continue