Add Icons to GUI menus

Given the handle of a GUI, this function attaches the icons stored in the "UserData" of each menu handle to the figure. As a result, the given GUI is enriched by properly implemented icons, added to the uimenu on the java level.

For the icons, filenames on the path, full qualified file names or java ImageIcon could be given.

Details can be found in the example.

USAGE:

% Attach icon data to the menu handles UserData

set(handles.Menu_File, 'UserData', '') % Also topevel handle could get the icon
set(handles.Menu_File_New, 'UserData', 'File_New.png')
set(handles.Menu_File_Load, 'UserData', 'File_Load.png')
set(handles.Menu_File_Save, 'UserData', 'File_Save.png') % get file on path
set(handles.Menu_File_Exit, 'UserData', 'File_Exit.png')

% Set the icons
Figure_Menu_Add_Icons(handles.Main)

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Aknowledgment: Some of the ideas used here are based on the great work of Yair Altman (http://undocumentedmatlab.com/) as presented in http://undocumentedmatlab.com/blog/customizing-menu-items-part-2/ and http://undocumentedmatlab.com/blog/customizing-menu-items-part-3/.