controls access to back office, along with SignIn, SignOut scripts

author | Ariel Sommeria-klein
package | Amfphp_Backoffice

### Methods

## checks if access should be granted, either because no sign in is required, or because the user is actually signed in.

    isAccessGranted()

note: must be called before output starts, as starting a session can change headers on some configs.

### Constants

## AMFPHP_ADMIN_ROLE

    AMFPHP_ADMIN_ROLE

## the field in the session where the roles array is stored

    SESSION_FIELD_ROLES