Add API to provide authentication options

[chargio]

API should provide the authentication options, with a label, along with the API version.
It should be part of the version API.

• Return the API version number
• Return a list of providers. Each one should have:
  • name: String with the name to be used.
  • type ("github")
  • icon_url
  • id_application
  • login_in_url
  • server
  • verify