Support of the .pp file extension for Pascal

This pull request adds the support of the .pp file extension for Pascal as requested in #297.
The original request was for Delphi but there is no distinction between Pascal and Delphi at the moment.

.pp is also the file extension of Puppet files.
Thus, I added sample files for both Puppet and Pascal with the .pp extension.

EDIT: I tested it on the repository from the original request: [tristan2468/PDFPrint](https://github.com/tristan2468/PDFPrint).