Cleaning up widget browser, renamed to Node_Browser.

fluid/CMakeLists.txt

fluid/app/fluid.cxx

fluid/app/undo.cxx

fluid/io/file.cxx

fluid/nodes/Fl_Function_Type.cxx

fluid/nodes/Fl_Grid_Type.cxx

fluid/nodes/Fl_Group_Type.cxx

fluid/nodes/Fl_Menu_Type.cxx

fluid/nodes/Fl_Type.cxx

fluid/nodes/Fl_Window_Type.cxx

fluid/panels/function_panel.cxx

fluid/panels/function_panel.fl

fluid/panels/settings_panel.cxx

fluid/panels/settings_panel.fl

fluid/panels/settings_panel.h

fluid/tools/autodoc.cxx

fluid/widgets/Bin_Button.cxx

fluid/widgets/Node_Browser.cxx

fluid/widgets/Node_Browser.h