[patch+test]: fix for matching paths with trailing slashes

Hello,

If you request a url like /foo/, the substitution in nest_app() fails because it doesn't account for the trailing slash.  This causes the Plack app to get the wrong PATH_INFO and SCRIPT_NAME.  Attached is a patch to fix the regex and a test case for basic.t.  Thanks for your effort on this module!  I'm trying to mash together a Web::Simple+Web::Machine app á la your blog with my Catalyst app, and this has been a big help.

Cheers,
Fitz