SVN commit 423208 by aseigo:

harmonize the remainder of the panel menu so that
special buttons and applets are handled uniformly in the UI
remove classes that this (and the Add Applet dialog) made redundant


 M  +17 -11    core/container_extension.cpp  
 M  +0 -1      core/panelextension.cpp  
 M  +2 -4      ui/Makefile.am  
 D             ui/addcontainer_mnu.cpp  
 D             ui/addcontainer_mnu.h  
 D             ui/addspecialbutton_mnu.cpp  
 D             ui/addspecialbutton_mnu.h  
 M  +26 -23    ui/removeapplet_mnu.cpp  
 M  +3 -4      ui/removeapplet_mnu.h  
 M  +7 -10     ui/removecontainer_mnu.cpp  
 M  +1 -1      ui/removecontainer_mnu.h  
 D             ui/removespecialbutton_mnu.cpp  
 D             ui/removespecialbutton_mnu.h