Patch by Moshe Weitzman:

- request_uri() behaves on non-apache web servers. i've tested on IIS and
apache (many platforms).

- modules may now implement the _search_item() hook which overrides the
default formatting of search results. modules already can customize which
fields are indexed. no module currently uses this hook but
externalpage.module expects to do so.

- added an optional $attribs argument to l(), lm(), and la() which is an
associative array of attributes which are inserted into the <a> tag (feature
#146).

- drupal_str_replace() is deleted (i had recently added it). i verified that
no scripts are currently calling this function. use strtr() or str_replace()
instead.

- arbitrary elements may be added to the <channel> and <item> blocks of an
RSS feed by passing the $args associative array. the core RSS engine is now
able to support elements like <cloud> and <catagory> [1] and RSS 1.0[2]

[1] http://backend.userland.com/rss092
[2] http://groups.yahoo.com/group/rss-dev/files/namespace.html