Support for basic auth

[pmcelhaney]

Counterfact doesn't currently read the security object of the OpenAPI schema.

When generating types, it should take that object into account.

For example, if the security object is defined as:

{
  "type": "http",
  "scheme": "basic"
}

Then Counterfact should read the username and add it to a $.user object.

Note: this only covers "http" authentication. OpenAPI also "apiKey", "mutualTLS", "oauth2", "openIdConnect". Eventually we'll want to support "apiKey" and "oauth2" as well. I'm not sure the others worth pursuing.

[pmcelhaney]

In the server, I think we need to look for either an Authorization header or a username / password in the URL, and parse out the username and password in a $.user object.

In the typescript generator, we need to include the $.user object if OpenAPI has a security object with type "http".

[pmcelhaney]

Should be working in 0.39

From this point, supporting other auth methods like API key should be pretty straightforward.