Add jwt crypto module, support unit test for config module

Signed-off-by:  Asai Neko<sugar@sne.moe>

config/types.go

@@ -9,6 +9,7 @@ type server struct {
 	Address    string `yaml:"address"`
 	DebugMode  bool   `yaml:"debug_mode"`
 	FileLogger bool   `yaml:"file_logger"`
+	JwtSecret  string `yaml:"jwt_secret"`
 }
 
 type database struct {