add generated main to aot

enabling generated main to have aot in ```lein ring uberjar``` to avoid:

```
Warning: specified :main without including it in :aot.
Implicit AOT of :main will be removed in Leiningen 3.0.0.
If you only need AOT for your uberjar, consider adding :aot :all into your
:uberjar profile instead.
```
(Leiningen 2.3.4)

regards,

Tommi