tkbio_layout_default: fix multicharacters
add sync target to Makefiles
tkbio: fix return code handling
- move TKBIO_RETURN_*, TKBIO_SYSTEM_*, struct tkbio_return to tkbio.h
- introduce handler return codes TKBIO_HANDLER_*
  - _handler_success: proceed
  - _handler_quit: quit app
  - _handler_defer: defer event back to lib
  - _handler_error: quit app with error, eg return _error|42;
- rename tkbio_handle_event -> tkbio_recv_event
- tkbio_handle_event: tkbio_recv_event + tkbio_handle_return(handler)
- tkbio_handle_return: handle defered events
  - _return_quit: close app
  - _return_signal: ignore, if sigint send _return_quit event
  - _return_system: send tsp cmds
- tkbio_handle_queue: tkbio_get_event + tkbio_handle_return(handler)
- rename tkbio_run -> tkbio_run_pfds
  - app owned pfds with more fd to check, spot 0 has to be unused
- tkbio_run: pfds + tkbio_run_pfds
- new tkbio_return_pollin/pollout/pollhuperr, gen by _run_pfds
- remove sigint, handled like other signals
- remove tkbio.gen_sigint: always sigint event
- type_button: remove tsp cmds, done when event defered