three-way merge with rust-url

https://github.com/servo/rust-url/blob/master/src/urltestdata.txt
remove duplicated test
Merge pull request #1293 from rubys/merge_with_rust

three-way merge with rust-url
Update test runner for changes in the manifest API.
Merge pull request #1298 from w3c/jgraham/runner_manifest_fix

Update test runner for changes in the manifest API.