Log Message:
Update emacs-snapshot to 24.0.50.20110526.

Notable changes:
	* textmodes/rst.el (rst-define-level-faces): Do not define face
	  symbol if it is already defined.
	* sha1.el: Remove. Function `sha1' is now builtin.
	* mail/sendmail.el: Require `rfc2047'.
	* Add an :exit-function for completion-at-point.
	* textmodes/bibtex.el: Convert to lexical binding.
	* <lots-of-files>.el: Don't quote lambda expressions with `quote'.