Allow PHP8.

(cherry picked from commit b9b8483)

Prepare 5.7.0 release

Bug fix for PHP 7.2

Merge pull request facebookarchive#942 from yguedidi/prepare_5_6_2

Prepare 5.6.2 release

Fix doc block syntax that interferes with Doctrine

Bump Graph API version to v2.10

* Added support for options with batch requests.

* Bumped Graph API version to v2.9.

Add a MIME type for SRT files

Fix a bug that would throw a type error in `GraphEdge` in some cases

Add check for PHP 7 CSPRNG first to keep mcrypt deprecation messages …

…from appearing in PHP 7.1 (facebookarchive#692)