split into src and lib and socket changes

* libanthracite files are now all in lib/
* anthracite-bin + anthracite-api-bin files are now all in src/
* socket split into header and source properly

lib/backends/file_backend.hpp

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "backend.hpp"
+
+namespace anthracite::backends {
+
+class file_backend : public backend {
+private:
+  std::unordered_map<std::string,std::string> file_cache;
+  std::string file_dir;
+  
+  std::unique_ptr<http::response> handle_request_cache(http::request& req);
+  void populate_cache_dir(std::string dir);
+  void populate_cache();
+public:
+  file_backend(std::string dir = "./www") ;
+
+  std::unique_ptr<http::response> handle_request(http::request& req) override;
+  std::unique_ptr<http::response> handle_error(const http::status_codes& error);
+};
+
+};