Allow false query parameters

[aaronfullerton]

Currently, when passing a boolean query parameter with a value of false to http, the following error surfaces:

 TypeError: value.map is not a function
      at formatValue (src/http.js:171:16)
      at src/http.js:187:36
      at Array.reduce (native)
      at encodeFormOrQuery (src/http.js:182:42)
      at Context.<anonymous> (test/http.js:218:14)

This PR resolves this error by adding a boolean type check in the formatValue function.

[shockey]

LGTM

[shockey]

Thanks for the PR, @aaronfullerton! Appreciate you taking the time to fix that issue.