Adding new `has` Eloquent functionality. `Sort` method on support Collection.

+- Added `has` method for checking the quantity of related models from
a parent query.
+- Added `sort` method to support `Collection` class.
Fix phpdocs

Mostly fully qualified namespaces, incorrect classes or wrong/missing
return values.
Implementing save() method on the BelongsTo relationship
Remove automatic key setting in Eloquent lists, as it causes problems. Fixes #1069.
Added `visible` property to Eloquent that is white-list version of `hidden`. Closes #1029.
Using `pluck` on Eloquent queries will now call accessors. Fixes #949.
Tweaked the behavior of the `has` method. Fixed method location. Closes #666. Closes #1112.
Check for results before returning in aggregate. Closes #1113.
Renaming save() to associate() and removing the save-ing of the parent model
added dictionary method to eloquent collections and wrote a test for it
Added `DB::reconnect` method to `DatabaseManager`. Closes #907.
changed method name from dictionary to model keys
Fix bug causing `increment` calls on model instances to update the whole table. Fixes #890.
Merge pull request #1121 from kapv89/eloquent-dictionaries

added dictionary method to eloquent collections
Refactor some code.
Merge pull request #1101 from stephenfrank/feature/BelongsTo-save

[Proposal] Implement save() method on the BelongsTo relationship
Added `associate` method to the `BelongsTo` relationship.
Added ability to register connections in the IoC container. Closes #851.
Added `Schema::hasColumn` method. Closes #826.
Added a basic "Capsule" implementation.