better conditional handling fixes #17 and more updateItem tests

Now `expected`, or conditionals, looks a lot like how keyConditions works and how query filter will look in #19 

```
    {expected: { akey: { EQ : 'hi'  }}

    {expected: { akey: { BETWEEN : [0, 5]  }}
```

Another breaking change is how delete is handled in updateItem. It will be an array instead of hash. 

```
    var key = { id: 'yo', range: 5 };

    // OLD WAY 
    var d = dyno.updateItem(key,  {delete: [{'thatkey':'THIS VALUE DOESNT MATTER'}]}, function() {....});

    // NEW WAY
    var d = dyno.updateItem(key,  {delete: ['thatkey']}, function() {....});
```

This also updates some tests for updateItem conditionals that had been commented out for.