Restruct logger order

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

config/config.go

@@ -1,10 +1,11 @@
 package config
 
 import (
-	"log"
 	"os"
 	"strings"
 
+	log "github.com/sirupsen/logrus"
+
 	"github.com/spf13/viper"
 )
 

config/types.go

@@ -16,7 +16,6 @@ type server struct {
 	Address     string `yaml:"address"`
 	ExternalUrl string `yaml:"external_url"`
 	DebugMode   string `yaml:"debug_mode"`
-	FileLogger  string `yaml:"file_logger"`
 }
 
 type database struct {