create the new FileServer and HandleDir, deprecate the rest APIBuilder/Party static methods and more

relative: https://github.com/kataras/iris/issues/1283 and removing pongo2 from vendor: https://github.com/kataras/iris/issues/1284

Former-commit-id: 3ec57b349f99faca2b8e36d9f7252db0b6ea080d

middleware/logger/config.go

@@ -68,7 +68,10 @@ type Config struct {
 	// LogFunc is the writer which logs are written to,
 	// if missing the logger middleware uses the app.Logger().Infof instead.
 	// Note that message argument can be empty.
-	LogFunc func(now time.Time, latency time.Duration, status, ip, method, path string, message interface{}, headerMessage interface{})
+	LogFunc func(endTime time.Time, latency time.Duration, status, ip, method, path string, message interface{}, headerMessage interface{})
+	// LogFuncCtx can be used instead of `LogFunc` if handlers need to customize the output based on
+	// custom request-time information that the LogFunc isn't aware of.
+	LogFuncCtx func(ctx context.Context, latency time.Duration)
 	// Skippers used to skip the logging i.e by `ctx.Path()` and serve
 	// the next/main handler immediately.
 	Skippers []SkipperFunc
@@ -83,15 +86,16 @@ type Config struct {
 // LogFunc and Skippers to nil as well.
 func DefaultConfig() Config {
 	return Config{
-		Status:   true,
-		IP:       true,
-		Method:   true,
-		Path:     true,
-		Query:    false,
-		Columns:  false,
-		LogFunc:  nil,
-		Skippers: nil,
-		skip:     nil,
+		Status:     true,
+		IP:         true,
+		Method:     true,
+		Path:       true,
+		Query:      false,
+		Columns:    false,
+		LogFunc:    nil,
+		LogFuncCtx: nil,
+		Skippers:   nil,
+		skip:       nil,
 	}
 }
 

middleware/logger/logger.go

@@ -100,6 +100,9 @@ func (l *requestLoggerMiddleware) ServeHTTP(ctx context.Context) {
 	if logFunc := l.config.LogFunc; logFunc != nil {
 		logFunc(endTime, latency, status, ip, method, path, message, headerMessage)
 		return
+	} else if logFuncCtx := l.config.LogFuncCtx; logFuncCtx != nil {
+		logFuncCtx(ctx, latency)
+		return
 	}
 
 	if l.config.Columns {