Change command-line parsing (again...)

- Added formatted table with `--style` option
- Added `warning` log level
- Fixed bugs and cleaned up API
- Removed some extra debugging output

include/error.hpp

@@ -13,6 +13,8 @@ namespace gdpm::constants::error{
 		NONE = 0,
 		UNKNOWN,
 		UNKNOWN_COMMAND,
+		UNKNOWN_ARGUMENT,
+		ARGPARSE_ERROR,
 		NOT_FOUND,
 		NOT_DEFINED,
 		NOT_IMPLEMENTED,
@@ -102,6 +104,11 @@ namespace gdpm{
 #endif
 		}
 
+		static constexpr gdpm::error error_rc(const gdpm::error& e){
+			error(e);
+			return e;
+		}
+
 		static void error(const char *p, const gdpm::error& e){
 			println("{}{}{}", p, prefix.contents, e.get_message());
 		}