This searches the region for identical lines, and removes all but one
copy of each repeated line. The lines need not be sorted.
+---
+** `blink-matching-paren' now only highlights the matching open-paren
+by default, instead of moving cursor. Set this variable to `jump' to
+enable the old behavior.
+
\f
* Changes in Specialized Modes and Packages in Emacs 24.4