package: update dependency versions
executor: remove `Base` arg from model function

Simplify the contract for functions exported by `models/*.js` files
by removing the second argument `Base`. The base class can be accessed
using `ModelCtor.base`.

An updated example of a model js file:

```js
module.exports = function(Customer) {
  Customer.setup = function() {
    Customer.base.setup.apply(this, arguments);
    // etc.
  };
};
```
Merge pull request #26 from strongloop/feature/simplify-model-fn-signature

executor: remove `Base` arg from model function