Add option to disable management of rundir

[tmanninger]

I am using php7.4 from sury on debian 10.
After every server reboot, this module creates the /var/run/php-fpm directory (which is not used by php-fpm) and triggers a reload, which resets all open connections to the php-fpm daemon.

This PR added an option to disable the managing of the /var/run/php-fpm directory

[kenyon]

Why are we managing this directory if it's not used? Maybe there is a better solution here, like making it conditional on some version of package or OS?

[tmanninger]

We are using /var/run/ and i wouldn't manage this directory with the puppet-php module.

[tmanninger]

It there no way to merge this MR?
I am using the PHP package from packages.sury.org, and i don't know, which OS versions and PHP versions are affected.
I think the best way is it to make it configureable.

[kenyon]

Seems OK to me. We'll want to rebase when merging this to eliminate the merge commit.

[tmanninger]

@kenyon i removed the merge commit

[tmanninger]

@smortex i added the documentation

[tmanninger]

@smortex is everything fine?

[smortex]

This feel weird, but I don't know what this directory is used for and the default behavior is unchanged so LGTM 🤷.

[smortex]

CI failure seems unrelated, merging