Enhancements to Revel command

Reformat of code
Allow user to use a mix of command line arguments and flags
Enhance the import tool to detect missing packages in the modules side
Added test cases for all commands

skeleton/app/controllers/app.go

@@ -0,0 +1,13 @@
+package controllers
+
+import (
+	"github.com/revel/revel"
+)
+
+type App struct {
+	*revel.Controller
+}
+
+func (c App) Index() revel.Result {
+	return c.Render()
+}