fix(tests): extract getRaw() helper, to allow fetching HTML pages (#468)
fix(tests): extract getRaw() helper, to allow fetching HTML pages (#468)

## Problem

In order to write approval tests on the features covered by `userLibrary.js`, it would be nice if the `api-client` helper provided a method to fetch HTML pages too.

## Proposed solution

- extract `getRaw()`, to allow fetching HTML pages
- make `get()` use `getRaw()`
- fix, while we're at it: in case of JSON parsing error, pass that error to the callback instead of printing it to console and returning the unparsed body
openwhyd/openwhyd,openwhyd/openwhyd,openwhyd/openwhyd,openwhyd/openwhyd,openwhyd/openwhyd