Feature request: Add at least "NOT" (regular expression) to filters

[bnspy]

With the current functionality of the filter it is laborious to establish the following rule:

Sync everything, exept everything in the directory ~/library which is not in the directory ~/library/mail.

A "not", or regular expressions in general, would be helpfull. So that something like
~/library/^(mail)/* in "exlude" would be possible.

The only way I see, to establish this task, is to exclude explicitely all subdirectores of ~/library exept the mail directory.

[Zenju]

The best way to solve this with FreeFileSync is to use two folder pairs:

1. sync everything except "~/library"
2. sync ~/library/mail