Log Message:
Update to librep-0.91.0.

0.91.0
======
   * Update note [important]:
     You need to rebuild rep-gtk and sawfish against this version of
     librep, because of an ABI-change.
     Your lisp files have to be byte-compiled again, too.
   * Halfway improved `debug-on-error' and `backtrace-on-error' [Teika
     Kazura]
   * When you evaluate a closure interactively, the module it belongs
     to is printed, too. [Teika kazura]
   * Improved functions' docstring support [Teika Kazura]
   * New function `subr-structure' [Teika Kazura]
   * Major documentation revision [Teika kazura]
   * `define-special-variable' is replaced by `defvar-setq' [Teika
     kazura]
   * Makefile's uninstall rule has been fixed [Christopher Bratusek]

0.90.6
======
   * renamed `file-uid-p' to `file-uid' and `file-gid-p' to `file-gid'
     [Christopher Bratusek]
   * Minor doc improvements [Teika Kazura]
   * improved specfile [Kim B. Heino]
   * Process execution failure emits better message. [Teika Kazura]