Add test example for Puppet

Currently, the detector is unable to match parameterized classes, so it
ends up detecting these are Pascal (since that's the default for .pp). This
adds an example: a class that is has both parameters and inherits (not
exactly a recommended practice, but a complex example).
Add detection of parameterized Puppet classes

This change expands one of the regular expressions used to disambiguate
Puppet and Pascal files ending with ".pp". Without this, parameterized
Puppet classes do not match and end up being detected as Pascal.

I have confirmed that this regular expression matches everything in my
Puppet tree that it matched with the previous, and all that failed to
match but should have, save one -- a file with nothing but comments.