allow to exclude path for meta-header

|Q            |A  |
|---          |---|
|Bug Fix?     |no |
|New Feature? |yes|
|BC Breaks?   |no |
|Deprecations?|no |
|Tests Pass?  |yes|
|Fixed Tickets|   |
|License      |MIT|

This add the originally requested feature for excluding files for the `meta:header` command - #277 

Sent using [Gush](https://github.com/gushphp/gush)
this is sick :+1: