Add per-user default policy and change policy application order.

The order is now the following

1) User protocol policy
2) User category policy
3) User default policy

The "not assigned" user policies are not a fallback any more.
They are only applied on not assigned devices.

scripts/lua/modules/http_lint.lua

@@ -1106,6 +1106,7 @@ local known_parameters = {
    ["per_ip_pass_rate"]        =  validateNumber,
    ["per_ip_slow_rate"]        =  validateNumber,
    ["per_ip_slower_rate"]      =  validateNumber,
+   ["user_policy"]             =  validateNumber,
 
    -- json POST DATA
    ["payload"]                 =  validateJSON