Document instrument Node.js config options
Document instrument Node.js config options

These config options were added in PR
https://github.com/appsignal/appsignal-nodejs/pull/664

Part of issue
https://github.com/appsignal/appsignal-nodejs/issues/519

I've specified the keys as their "Ruby style" names initially and
overwritten the `config_key` field in the Node.js section. This follow
the standard set by other config option definitions. These only look
weird because they have no counterpart in other languages (yet).

I've removed "Default is true." from the descriptions, because this is
already listed in the "Default value" row on the page.

appsignal/appsignal-docs