Added classes IApiRequest, ApiRequest, HttpApiRequest.

src/api/Api.h

@@ -35,6 +35,7 @@ namespace xmrig {
 class Controller;
 class Httpd;
 class HttpRequest;
+class IApiRequest;
 class String;
 
 
@@ -55,6 +56,7 @@ protected:
     void onConfigChanged(Config *config, Config *previousConfig) override;
 
 private:
+    void exec(IApiRequest &request);
     void genId(const String &id);
     void genWorkerId(const String &id);