Ignore permalink option in metadata of a particular file

[rahulkgupta]

It would be nice to be able to ignore the permalinks plugin for specific files. For my use case, aws s3 allows for a static site hosting and can take a top level error.html file as the generic error page. I want to have the error page to not be permalinked. I also would like to take advantage of the template approach, so I don't have to make a unique error.html file in my source directory.

The top yaml of the error.md file would be something like

---
template: error.html
title: error
permalinks-ignore: true

---

[rahulkgupta]

#19