Email notification delay should have an option to be shortened

[angerized]

Steps to reproduce

1. Create a share with another user
2. Recipient is informed of this way too late

Expected behaviour

At the very least shorten the notification delay (maybe add a 15 minutes option).
Idealy recipients should be informed instantly.

Actual behaviour

Recipient is informed over an hour after the share has been established.

Server configuration

Debian 9 64 bits
Nextcloud 12.0.2 fresh install
MariaDB 10.1.26
PHP 7

[angerized]

On this page @Rello suggested to open a pull request with other options. I'm not sure how to do this. But I suppose the code could look something like that:

email_batch_time = 3600;
if ($notify_setting_batchtime === UserSettings::EMAIL_SEND_FIFTEENMINUTES) {
$email_batch_time = 900;
} else if ($notify_setting_batchtime === UserSettings::EMAIL_SEND_DAILY) {
$email_batch_time = 3600 * 24;
} else if ($notify_setting_batchtime === UserSettings::EMAIL_SEND_WEEKLY) {
$email_batch_time = 3600 * 24 * 7;
}

[MorrisJobke]

This will be fixed in 12.0.3 There will be a dedicated sharing email.