(#304) Fix double backticks in Markdown

[danielparks]

Previously, some values in generated Markdown were wrapped in double backticks instead of single backticks. This removes the code that added the extra backticks.

See #304.

[binford2k]

are there other parts of the codebase that might be affected by this?

[danielparks]

I don’t think so. It appears that the value_string function was added (1374b67) before backticks were used for all values, and then it was left in place (07ef004). I removed all calls to it.

It’s possible that some of the litmus acceptance tests will start failing because of this, but I didn’t find any tests for double backticks, or that called value_string directly. Unfortunately, it’s pretty easy to accidentally generate Ruby code that doesn’t show up in a search for such things.

Also unfortunately, the litmus tests seem to be broken both here and on my machine. :( I got Litmus working in my own module with vagrant, but it took a lot of digging, so I’m not terribly optimistic that will be easy to figure out without an expert.