Fix races / finally remove global app for good (#7570)

* finally remove global app for good

* test compilation fixes

* fix races

* fix deadlock

* wake up write pump so it doesn't take forever to clean up

app/job_test.go

@@ -12,6 +12,7 @@ import (
 
 func TestGetJob(t *testing.T) {
 	th := Setup()
+	defer th.TearDown()
 
 	status := &model.Job{
 		Id:     model.NewId(),
@@ -32,6 +33,7 @@ func TestGetJob(t *testing.T) {
 
 func TestGetJobByType(t *testing.T) {
 	th := Setup()
+	defer th.TearDown()
 
 	jobType := model.NewId()