core: rework request rules

fixes #21

example/config.jsonc

@@ -26,17 +26,24 @@
     // NOT recommended to set to anything below 4 or above 5.
     "default_challenge_difficulty": 4,
 
-    // specific ip range configs.
-    "ip_configs": [
+    // specific rules. They are checked top to bottom, and the first one to match will determine the request's fate
+    "rules": [
         {
             "action": "ALLOW",
             "ip_ranges": [
                 "127.0.0.1/24",
                 "::1/128"
-            ],
-            // if this regex matches the resource requested, a different rule will be applied
-            "exclude_regex": ".*/commit/.*",
-            "action_on_exclude": "DENY"
+            ]
+        }, {
+            "action": "DENY",
+            "user_agent": ".*(bot).*"
+        }, {
+            "action": "DENY",
+            "resource": "(/secret/).*"
+        }, {
+            "action": "CHALLENGE",
+            "difficulty": 5, // quite damn hard!
+            "resource": "(/hard/).*"
         }
     ],