+ Initialise the char buffers in the X11 driver.
  * src/io.c:
    + caca_get_event() and caca_wait_event() immediately return zero if
      event_mask is zero.
    + Added support for the Home, End, PgUp and PgDown keys.
    + In the S-Lang driver, added a call to SLang_getkey() before the call to
      SLkp_getkey(), otherwise a single Escape call will not be interpreted.
  * test/event.c:
    + The "quit" sequence now quits the program, instead of "q" alone.
    + Added a status bar below.