pass along extra requests when performing real network hit
handle extra args for internal mappings
changelog
explain what these tests are doing
Merge branch 'topic/fix_mirror'

Fixes issues like ->mirror('http://london.pm.org', 'file') (RT#84094)
Test-LWP-UserAgent-0.016

          - fixed handling of methods such as mirror() (RT#84094) - thanks for
            the report, Tom Hukins!