Introducing idToken and oauthToken

Allow the user to configure the service so any of the 3 possibles can be reached
when the user passes webApiKey in the credentials dictionary will get a JWT token
id, if androidApiKey is set in the credentials then an off-line capable oauth2
token bearer will be generated in the oauthToken value, while if no argument is
set a simple oauth2 token will get generated.
Adding extra necessary permissions