Extension of the token pattern syntax

[MCR-Prototype]

Hello,
I am very satisfied with the functionality of maska. But we have encountered a small problem. We would like to
allow to enter own and suggested values in a dropdown menu.(Own entered values have a different pattern than the suggested ones) So we wanted to extend the validation. Unfortunately it is not possible to extend the regex via a hook to validate the suggested values via regex or to extend the pattern via a "|" to use the token system. A nice extension would be to give the pattern a possibility to have an "or" available. The "|" is unfortunately already used to split the pattern parts.