Leading space is being stripped from "From" path; proposed fix

If the From field contains a leading space, it is being stripped, making it impossible to redirect to the same path without the leading space.

For example, an external site is pointing to "mysite.com/ alias/fullpath", with a space before 'alias'. The From field is set as " alias/fullpath" and To is set as "alias/fullpath", but the module thinks these are identical.

A quick fix was to remove the space from the trim mask in redirect.module, line 1310:
$url = trim($url, " \t\n\r\0\x0B\/");

The problem is, any trailing spaces will cause the redirect to fail, since browsers will strip them when the URL is entered. To resolve this, rtrim was added specifically to remove trailing whitespace, resulting in the following proposed fix:
$url = rtrim(trim($url, "\t\n\r\0\x0B\/"), " ");