Changes

*toolbar,

*toolbar,

*a series of tabs, one for each module, an add module button, and an open example module button,

*a series of tabs, one for each module, an add module button, and an open example module button,

*within each module, a series of tabs, one for __doc__ that is not editable, one for each source file that is editable, and an add file button,

*within each module, a series of tabs, one for __doc__ that is not editable (only if the module has non-empty __doc__), one for each source file that is editable, and an add file button,

*within each file, a syntax highlighting text edit widget.

*within each file, a syntax highlighting text edit widget.