support multi-module (#4)

* add multimodule
* re-package modules

server/internal/router/router_export_test.go

@@ -0,0 +1,11 @@
+package router
+
+import (
+	"github.com/gin-gonic/gin"
+	"github.com/iliadenisov/galaxy/server/internal/router/handler"
+)
+
+func SetupRouter(e handler.CommandExecutor) *gin.Engine {
+	gin.SetMode(gin.TestMode)
+	return setupRouter(e)
+}