Log Message:
Update to st-0.6.

Changes:
* direct tty line support
   * "st -l /dev/ttyS0 115200" works
   * replace your screen(1) with st
* backspace and delete now work like the Linux standard
   * you only need to change the defaults if you are using a real
     hardware terminal
* much code refactoring
* the -g(eometry) flag now behaves like in xterm
* the main loop now uses a monotonic clock to prevent bugs tickling
    down from a flawed time scale reality
* invisible attribute is now supported
* struck-out attribute is now supported
* many wide-character bugs are fixed
* fix XIM in st
* new sequences:
   * CAN, ESC, LS2, LS3, DECSCUSR
   * 8bit: DECID, NEL, HTS, DCS, APC, PM, OSC
* children now show an error message
* VT102ID can be configured in config.h
* fix shell selection by grasping the value from the passwd file
* don't allow shells run by users not in passwd
* st supports utmp
* the bell in st now calls XkbBell so it's possible to catch the
    XkbBellNotifyEvent for your own pleasure 
* many changes in the font drawing code
   * speed optimisations!
* clipboard handling has been fixed
   * default is primary
   * clipboard needs shortcuts
* MANY small fixes to make st more stable