Fix some small syntax errors in the Review Board docs.

Review Request #8670 — Created Jan. 26, 2017 and submitted — Latest diff uploaded

Information

Review Board
release-2.5.x
341bf1e...

Reviewers

We had a few references and string literals that were broken, causing
errors when building the Review Board documentation. This fixes those
errors, and converts one set of string literal to file references.

Built the docs without errors.