CAS Authentication Adapter for ReCodEx

External authentication component that connects ReCodEx to CAS. This is basically a standalone application that handles CAS authentication (using native PHP CAS library). When the user is authenticated, it creates a JWT token that is passed via redirect back to ReCodEx in URL. The token holds the following items in payload:

• iat - timestamp when the token was issued
• id - external (CAS) identification of the user (e.g., UKCO in case of cuni.cz CAS).
• firstName, lastName and mail address of the user
• role identifier based on user's affiliations (rules are defined in config)
• instanceId - if set in config (this is a simple mechanism that will allow ReCodEx to create the user on first sign-in)

The secret key used to sign the token must be shared with ReCodEx in configuration.