Coverity check on master@bd16929, CID 71395: Uninitialized scalar variable

umbrello/uml.cpp function UMLApp::slotFind()
- Coverity reports:
  > UNINIT
  > Using uninitialized value count when calling i18np.
  Solution: Initialize `count' to 0.
- Furthermore, replace call to i18np() by i18n() because "found" does not
  have a plural form.