Replace/alias "new" command with "init"

This is purely an aesthetic/convention issue.

I think it's safe to say that the prevailing convention that scaffolding applications with CLIs that are packaged as NPM modules use the command "init" for initialization.

Using the command...

```
> $ osprey new
```

...just feels less node-like than using...

```
> $ osprey init
```

:-)
