setup menu (input devices section) by using standard button gadgets
* added support for mouse scroll wheel (caused buggy behaviour before)
* added support for scrolling horizontal scrollbars with mouse wheel by
- holding "Ctrl" button pressed while scrolling the wheel
+ holding "Ctrl" key pressed while scrolling the wheel
+ * added support for single step mouse wheel scrolling by holding "Alt"
+ key pressed while scrolling the wheel
* changed output file "stderr.txt" on Windows platform now always to be
created in the R'n'D sub-directory of the personal documents directory
* added Windows message box to direct to "stderr.txt" after error aborts