PLT-6471 Properly panic when translations can't be loaded (#6414)

* PLT-6471 Properly panic when translations can't be loaded

* Print usage messages when errors occur during CLI initialization

* Reverted behaviour of FindDir and added second return value to it

* Fixed merge conflict

app/user.go

@@ -709,7 +709,8 @@ func CreateProfileImage(username string, userId string) ([]byte, *model.AppError
 
 	initial := string(strings.ToUpper(username)[0])
 
-	fontBytes, err := ioutil.ReadFile(utils.FindDir("fonts") + utils.Cfg.FileSettings.InitialFont)
+	fontDir, _ := utils.FindDir("fonts")
+	fontBytes, err := ioutil.ReadFile(fontDir + utils.Cfg.FileSettings.InitialFont)
 	if err != nil {
 		return nil, model.NewLocAppError("CreateProfileImage", "api.user.create_profile_image.default_font.app_error", nil, err.Error())
 	}