Fixed some @return in PHPDocs

The return type is copied from the php.net manual
Fixed another one

requireOnce()
Add "splice" method to collection.
Added field referencing to before and after validators
Added tests for the before validator
View data accessors return by reference
Merge pull request #1824 from shachibista/master

Added ability to reference fields in before and after validators
Removed extraneous comments
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Merge pull request #1829 from phpmycoder/bug/view-data-accessors-returns-reference

View data accessors return by reference
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Merge pull request #1816 from KaneCohen/splice

Add "splice" method to collection.
Update change log.
Merge pull request #1803 from ChristianGaertner/master

Fixed 3 @return in PHPDocs for Illuminate\Filesystem\Filesystem