Fixes failing tests in PHP 5.3 from f942de6.

No math required to check if NAN is identical to a value.
Closes #816
Merge pull request #811 from whatthejeff/php53_nan_identical

Fixes failing tests in PHP 5.3 from f942de6.
Updated ChangeLog
Merge branch '3.7'

Conflicts:
	ChangeLog.md
	composer.json
Updated ChangeLog