* stdwinmodule.c: various new commands: setwin{pos,size},

listfontnames, bitmap ops.
* listobject.c: use mkvalue() when possible; avoid weird error when
  calling append() without args.
* modsupport.c: new feature in getargs(): if the format string
  contains a semicolor the string after that is used as the error
  message instead of "bad argument list (format %s)" when there's an
  error.