fix slider
tkbio: draw text on buttons
- tkbio_fb: text drawing functions
- add bitmap font iso_font.h
- type_button: draw text if not copy
- menu: add names to buttons
tkbio: add text alignment
tkbio: refactor #4
- tkbio_layout: mapelem
  - remove connect
  - create options
  - move options from type to options
  - move connect to options
  - new options align_*
- type_button: use align from mapelem for drawing text