* add sub document aggregation array functionality

example:
    Model::sum('subarray.*.price');

this method is much simpler as to use as complex raw aggregations

for this function a $unwind directive will be pushed in pipeline before $group

* change testSubdocumentArrayAggregate

change test for different scenarios

* rebase to latest master and fix style ci issues

* Remove dependency on Laravel Application

* styleci

* Filling with Dot-Notation Keys

Simply override `removeTableFromKey($key)` method and  just return original keys in order to support dot-notation when calling `fill` on model.

* Style CI

* Dot-Notation Fill Tests

* Fix collections attachments.

If you will try to attach model simultaneously to a collection of related models, you'll crash your app, because this method will try to operate with models themselves but not with their ids.

This change considers every case and fixes collections relations.

* Fix typo

* Fixes #789

* StyleCI fixes

* StyleCI fixes

* StyleCI fixes

Laravel 5.3 support currently is available for 3.1.0-alpha release only!

* Adding sparce & unique indices

Provides a handy workaround for issue 556.

* Code styling fix

This addresses the issues highlighted in the StyleCI analysis.

5.3 UnitTests

updated config file path

Initial support laravel 5.3