Adding default to QT4 requirement for radixplot.

radixplot/cmake/Dependencies.cmake

@@ -3,6 +3,10 @@
 ## Jordan P. Lefebvre
 ## Tuesday May 31 12:57:18 2016
 ##---------------------------------------------------------------------------##
+IF(NOT USE_QT5)
+   SET(USE_QT4 ON)
+ENDIF()
+
 IF(USE_QT4)
    SET(QT_PACKAGES QT)
 ELSE()