Optimized upstream & loadbalancer

- Test and optimized load balancer origin picker
- Fixed no active origin cannot load proxy rule bug
- Implemented logger design in websocket proxy module
- Added more quickstart tours
- Fixed #270 (I guess)
- Fixed #90 (I guess)

src/mod/dynamicproxy/router.go

@@ -70,6 +70,11 @@ func (router *Router) PrepareProxyRoute(endpoint *ProxyEndpoint) (*ProxyEndpoint
 
 // Add Proxy Route to current runtime. Call to PrepareProxyRoute before adding to runtime
 func (router *Router) AddProxyRouteToRuntime(endpoint *ProxyEndpoint) error {
+	if len(endpoint.ActiveOrigins) == 0 {
+		//There are no active origins. No need to check for ready
+		router.ProxyEndpoints.Store(endpoint.RootOrMatchingDomain, endpoint)
+		return nil
+	}
 	if !router.loadBalancer.UpstreamsReady(endpoint.ActiveOrigins) {
 		//This endpoint is not prepared
 		return errors.New("proxy endpoint not ready. Use PrepareProxyRoute before adding to runtime")