Clarify usage with Enterprise instances

Could the README be amended to include instructions for using this extension with GitHub Enterprise instances? I’ve seen in other places (https://github.com/Microsoft/vscode-pull-request-github/issues/368#issuecomment-419890132) that this is intended to work.

I’ve tried generating a personal access token, and supplied it along with the URL for our instance and my username:

"github.hosts": [
	{
		"host": "HOST",
		"username": "USERNAME",
		"token": "TOKEN",
	}
]

But after reloading username and token are stripped, and I’m prompted to use the regular signin process, which doesn’t work:

"github.hosts": [
	{
		"host": "HOST",
	}
]

And the thing is that I can’t figure out whether this is an user error or a bug (I’ve installed version 0.1.1).

[shana]

Thanks for the info, I’ll try to repro internally and get a fix going for y’all. Sorry for the trouble!

[thorntonrose]

My GitHub Enterprise instance uses SSO. When I attempt to sign in from VSCode, I get a page with a “Continue” button. When I click that button, I get a 404 (URL = https://<host>/login/oauth/authorize?state=action%3Acode%3Bguid%3A6652a2c3-3f81-46bb-bda8-dcb61b94e933&scope=read…). The plugin is configured with host, username, and token.