functions: performance improvements - LRU & singleflight DB calls (#322)

* functions: add cache and singleflight to ease database load

* runner: upgrade

* deps: upgrade glide files

* license: add third party notifications

* functions: fix handling of implicitly created apps

* functions: code deduplication

* functions: fix missing variable

api/runner/async_runner_test.go

@@ -182,7 +182,7 @@ func TestTasksrvURL(t *testing.T) {
 	}
 
 	for _, tt := range tests {
-		if got, _ := tasksrvURL(tt.in); got != tt.out {
+		if got := tasksrvURL(tt.in); got != tt.out {
 			t.Errorf("tasksrv: %s\texpected: %s\tgot: %s\t", tt.in, tt.out, got)
 		}
 	}