links include source path when base url is set

[joshbeard]

When running with --base-url specified

web-indexer --config /deploy/web-indexer.yml --base-url 'https://get.dev.foo.bar'

With a config like this:

source: /mnt/repos
target: /mnt/repos
link_to_index: false
relative_links: true
title: get.dev.foo.bar - {relativePath}
recursive: true
minify: true
order: desc

The links have the source in them - e.g. https://get.dev.foo.bar/mnt/repos/sub