Sign-On-O-Tron support

[rlafferty05]

• Added support for the Sign-On-O-Tron oauth2 provider. Information about it can be found here.
• Changed the javascript require to use httpswwwroot because the buttons weren't showing up on https login pages.

[mouneyrac]

Hi Ryan,
thanks for the pull request. How do I test it? Where do I find a Sign-On-O-Tron provider?

[rlafferty05]

Hi Jerome,
Sorry for the delay on getting back to you. If you can give me an email address we can set up an account for you to test it on the site I developed it for.

[mouneyrac]

Thanks Ryan, it seems like a good idea.

Otherwise where are the Sign-On-O-Tron docs? I know about nothing about this provider.

[rlafferty05]

Hi Jerome,
The signonotron code and documentation are here: https://github.com/alphagov/signonotron2
I've also written the provider class: https://github.com/LearningPool/oauth2-signonotron

[rabser]

Hi, i'm the new lead mantainer for this plugin and i'm going to release a new version, so i need to reconsider all the past merge requests.
In the new release i will update the phpleague client lib to the latest one: it seems that your code is ready for the 2.x release, but i need to double check everything before releasing and reading your past messages with Jerome, my email for enabling a testing account is sergio.rabellino@unito.it.

Thanks in advance.