Setting up stacker in new projects

Stacker is awesome for big projects but could be much better for smaller projects. I have some small projects I've wanted to use it for.

The workflow I think would be awesome to get to would be something like:

```
stacker init
stacker add dynamodb-table (maybe this prompts you for all the inputs?)
```

the above would generate the configs etc.

the cases i've hit is wanting a simple db for a project. i had to read up a bunch of stacker/troposphere things to do it. i would have loved something like the above.