- solidify/overlap.h, solidify/overlap.c (edit_top, overlap_edit): select
the face to rotate and shift
- solidify/overlap.c (scroll_event): select face to manipulate based on
edit_top
- solidify/solidify.c (a_b, gui_buttons): new button B+A to select the
bottom face for editing
- solidify/solidify.c clicked): call overlap_edit to select face to edit