Add test cases for the proxy, and do some tiny fixes.

the fixes are:
1. add "content-type" in headers for when dealing with localresponse
2. make a more accurate tip for throttle rate when lower than 1
3. make the crtMgr funcionality a more independent one
4. uppercase the request header before sending it out

update the tip

test/test_rules/shouldUseLocalResponseRule.js

@@ -0,0 +1,22 @@
+/*
+* Rule defination for shouldUseLocalResponse
+*
+*/
+
+const dealLocalBody = 'handled_in_local_response';
+
+module.exports = {
+    shouldUseLocalResponse: function (req, reqBody) {
+        return req.url.indexOf('uselocal') > -1;
+    },
+    shouldInterceptHttpsReq: function () {
+        return true;
+    },
+    dealLocalResponse: function (req, reqBody, callback) {
+        const header = {
+            'Via-Proxy-Local': 'true'
+        };
+
+        callback(200, header, dealLocalBody);
+    }
+};