Rename "[Mm]ethod(s)" to "[Ff]unction(s)"

Only methods as programming functions are affected. Besides renaming
some actions like "Switch Between Function Declaration/Definition" this
mostly touches (api) code comments.

This is a follow-up patch to commit 872bfb7.

Change-Id: Icb65e8d73b59a022f8885b14df497169543a3b92
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/cppeditor/cppeditor.cpp

@@ -1023,7 +1023,7 @@ void CPPEditorWidget::jumpToOutlineElement(int index)
     // the view's currentIndex is updated, so we want to use that.
     // When the scroll wheel was used on the combo box,
     // the view's currentIndex is not updated,
-    // but the passed index to this method is correct.
+    // but the passed index to this function is correct.
     // So, if the view has a current index, we reset it, to be able
     // to distinguish wheel events later
     if (modelIndex.isValid())