ENH: add some messages not errors for findqt

Modules/FindQt.cmake

@@ -123,11 +123,15 @@ ELSE(NOT QT3_INSTALLED AND NOT QT4_INSTALLED)
   IF(NOT QT_FOUND AND NOT DESIRED_QT_VERSION)
     IF(QT_REQUIRED)
       MESSAGE(SEND_ERROR "Multiple versions of QT found please set DESIRED_QT_VERSION")
+    ELSE(QT_REQUIRED)
+      MESSAGE("Multiple versions of QT found please set DESIRED_QT_VERSION")
     ENDIF(QT_REQUIRED)
   ENDIF(NOT QT_FOUND AND NOT DESIRED_QT_VERSION)
   IF(NOT QT_FOUND AND DESIRED_QT_VERSION)
     IF(QT_REQUIRED)
       MESSAGE(SEND_ERROR "CMake was unable to find QT version: ${DESIRED_QT_VERSION}. Set advanced values QT_QMAKE_EXECUTABLE and QT${DESIRED_QT_VERSION}_QGLOBAL_FILE.")
+    ELSE(QT_REQUIRED)
+      MESSAGE( "CMake was unable to find desired QT version: ${DESIRED_QT_VERSION}. Set advanced values QT_QMAKE_EXECUTABLE and QT${DESIRED_QT_VERSION}_QGLOBAL_FILE.")
     ENDIF(QT_REQUIRED)
   ENDIF(NOT QT_FOUND AND DESIRED_QT_VERSION)
 ENDIF(NOT QT3_INSTALLED AND NOT QT4_INSTALLED)