Remove dependency on request

[saltire]

Hi,

Why is this library still dependent on the request package? It's been deprecated for years, and is now triggering vulnerability warnings.

[cfroese]

Looks like it was introduced in d0fb470. The other changes in the commit do not strike me as requiring request. So maybe this is a straight forward removal from package.json.

[cfroese]

There's also a PR to address this: #366.