[WIP] Add BSON to CodableRouting benchmark

[djones6]

This PR uses OpenKitten's BSON encoder/decoder to add BSON content-type support to the CodableRouting benchmark.

Two lua scripts for wrk are provided, specifying a POST content-type and accept type of JSON and BSON, respectively. These can be used to POST the structure "value": "Hello World" to the /postHello route, which then echoes the same data back again with the requested content type.

This exercises Kitura's Content-Type and Accept type determination for Codable routing (Kitura/Kitura#1309) in order to select the appropriate encoder and decoder.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}