Function is_http_version

libi2pd/HTTP.cpp:46–49

	};

	static inline bool is_http_version(std::string_view str)
	{
		return std::find(HTTP_VERSIONS.begin(), HTTP_VERSIONS.end(), str) != std::end(HTTP_VERSIONS);
	}

	static inline bool is_http_method(std::string_view str)
	{