Fix unused parameter warnings and missing includes:

fix #127

* Added beast::detail::ignore_unused based on boost::ignore_unused
* Added -Wextra compilation flag when building with gcc
* Fixed all unused parameter warnings with ignore_unused
* Fixed all missing includes when building each .hpp separately

test/http/message_fuzz.hpp

@@ -10,6 +10,7 @@
 
 #include <beast/core/write_dynabuf.hpp>
 #include <beast/http/detail/basic_parser_v1.hpp>
+#include <beast/http/detail/rfc7230.hpp>
 #include <cstdint>
 #include <random>
 #include <string>

test/http/nodejs_parser.hpp

@@ -795,7 +795,7 @@ private:
 
     bool
     on_request(unsigned method, std::string const& url,
-        int major, int minor, bool keep_alive, bool upgrade,
+        int major, int minor, bool /*keep_alive*/, bool /*upgrade*/,
             std::true_type)
     {
         m_.method = detail::method_to_string(method);
@@ -826,6 +826,7 @@ private:
         int major, int minor, bool keep_alive, bool upgrade,
             std::true_type)
     {
+        beast::detail::ignore_unused(keep_alive, upgrade);
         m_.status = status;
         m_.reason = reason;
         m_.version = major * 10 + minor;

test/http/write.cpp

@@ -64,7 +64,7 @@ public:
         template<class ConstBufferSequence>
         std::size_t
         write_some(
-            ConstBufferSequence const& buffers, error_code& ec)
+            ConstBufferSequence const& buffers, error_code&)
         {
             auto const n = buffer_size(buffers);
             using boost::asio::buffer_size;
@@ -112,6 +112,7 @@ public:
             void
             init(error_code& ec) noexcept
             {
+                beast::detail::ignore_unused(ec);
             }
 
             template<class WriteFunction>