Move role related views to FAB Auth manager:

- List roles
- Edit role
- Create role
- View role
except ImportError:
            log.error("python-ldap library is not installed")
            return None
        try:
            
            if self.auth_ldap_tls_cacertdir:
                ldap.set_option(ldap.OPT_X_TLS_CACERTDIR, self.auth_ldap_tls_cacertdir)
            if self.auth_ldap_tls_cacertfile:
                ldap.set_option(ldap.OPT_X_TLS_CACERTFILE, self.auth_ldap_tls_cacertfile)
            if self.auth_ldap_tls_certfile:
                ldap.set_option(ldap.OPT_X_TLS_CERTFILE, self.auth_ldap_tls_certfile)
            if self.auth_ldap_tls_keyfile:
                ldap.set_option(ldap.OPT_X_TLS_KEYFILE, self.auth_ldap_tls_keyfile)
            if self.auth_ldap_allow_self_signed:
                ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_ALLOW)
                ldap.set_option(ldap.OPT_X_TLS_NEWCTX, 0)
            elif self.auth_ldap_tls_demand:
                ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_DEMAND)
                ldap.set_option(ldap.OPT_X_TLS_NEWCTX, 0)
            
            con = ldap.initialize(self.auth_ldap_server)
            con.set_option(ldap.OPT_REFERRALS, 0)
            if self.auth_ldap_use_tls:
                try:
                    con.start_tls_s()
                except Exception:
                    log.error(LOGMSG_ERR_SEC_AUTH_LDAP_TLS.format(self.auth_ldap_server))
                    return None
            
            user_dn = None