Release 0.3.9

[joshbruce]

Updated to be at same release number as 8fold-marked. Should resolve XSS, relative pathing, and some minor Bower build things.

Two tests failing: That’s probably my fault for merging something without confirming all tests were passing. Not sure how to troubleshoot. Checking out and committing to this branch should update the PR. Once the tests pass, will publish package.

• def_blocks.text failed at offset 20.
• relative_urls.baseUrl=http%3A%2F%2Fexample%2Ecom%2Fbase%2F.text failed at offset 267.

Would be nice to get a GitHub CI integration going.

@gibson042, @UziTech, @ankon

See also #956

Fixes #937
Fixes #926

[joshbruce]

Would really like to do this release. Cannot with merge conflicts and whatnot. I don't know enough about the codebase to do that, unfortunately. I did reach out to one of the developers on my other team who was able to analyze a bit, believe one of the tests was failing a while back.