[RDY] Extract cursor_shape.c from misc2.c and types/consts from structs.h

More work on #209 and closes #333.

 - Made `shape_table` static in `cursor_shape.c`
 - Compile with `CURSOR_SHAPE` turned on and solve syntax errors
 - Move `cursorentry_T` from `structs.h` to `cursor_shape.h`