Update FacebookResponse.php

Fixed paging attribute to "paging" and fixed "Cannot use object of type stdClass as array" error
fixed $url['path'] already contains api version
Fix Etag handling
Composer is a prerequisite for running the tests
Merge pull request #65 from dfabulich/patch-1

Composer is a prerequisite for running the tests
Merge pull request #60 from yguedidi/fix-etag-handling

Fix Etag handling
Merge pull request #55 from danielegrosso/master

[Bug Fix]  paging and sdtClass error on FacebookResponse.php