Add feature to allow fallback for failed email filters

As a system administrator, I would like for the email filtering system on the server to include a check: “If folder does not exist, do not move the email" so that I will have fewer users reporting missing emails due to incorrect filter creation.

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If a user sets up a filter to move mail to an different folder then later changes that folder name the email filter causes the emails to be moved to oblivion. cPanel should simply have a check: if folder not exists don't move email.

I'm sure many sys admins would love this as the "where's my email" question is an annoyance from users (is it it your spam?).