feat(ngRepeat): expose the iterating properties over the alias

Expose the properties `$index`, `$first`, `$middle`, `$last`, `$odd` and `$even` as part of the alias

Closes #9582
I know you're thinking "oh this is really clever because this way they can get the collection properties the same way", but it's not --- it can potentially shadow properties, which would be bad --- and it will make accessing collection properties this way slower.

Lets not do this.