Add Cronjobs to send Recurring invoices and reminder emails

Problem

Add Cronjobs to send Recurring invoices and reminder emails.

See: https://docs.invoiceninja.com/configure.html#recurring-invoices-and-reminder-emails

Solution

Added cronjobs
updated readme

PR Status

[x] Code finished.
[ ] Tested with Package_check.
[x] Fix or enhancement tested.
[x] Upgrade from last version tested.
[x] Can be reviewed and tested.

Package_check results

If you have access to App Continuous Integration for packagers you can provide a link to the package_check results like below, replacing '-NUM-' in this link by the PR number and USERNAME by your username on the ci-apps-dev. Or you provide a screenshot or a pastebin of the results

YunoHost-Apps / invoiceninja_ynh

Add Cronjobs to send Recurring invoices and reminder emails #2

Problem

Solution

PR Status

Package_check results