Log Message:
Update to 1.2.1:

Alan Coopersmith (2):
      config: Add missing AC_CONFIG_SRCDIR
      Combine usage message strings

Edward Sheldrake (1):
      Fix reading backlight level on 64-bit systems (bug 63205)

Julien Cristau (1):
      man: replace hyphens with minus signs

Matt Turner (1):
      xbacklight 1.2.1