v1.5.13

⚠️ Reminder: a new release of symfony1 does not mean you might use it for new projects. You MUST use Symfony 5 instead.

Most of changes for that release are for PHP 7.4 compatibility.
Also the package has been renamed to friendsofsymfony1/symfony1.

Merged PRs:

• Fix for Warning: ini_set(): A session is active... #229
• Php 7.4 Incompatibility Fixes #228
• Remove notice appeared on php 7.4 #230
• Rename package to friendsofsymfony1/symfony1 #231