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/tests/apptest.go

@@ -0,0 +1,23 @@
+package tests
+
+import (
+	"github.com/revel/revel/testing"
+)
+
+type AppTest struct {
+	testing.TestSuite
+}
+
+func (t *AppTest) Before() {
+	println("Set up")
+}
+
+func (t *AppTest) TestThatIndexPageWorks() {
+	t.Get("/")
+	t.AssertOk()
+	t.AssertContentType("text/html; charset=utf-8")
+}
+
+func (t *AppTest) After() {
+	println("Tear down")
+}