Verify a file's conformance with its modeline

[Rainer Müller]

Ryan Schmidt wrote:
> So then lint could warn if the modeline specifies a character  
> encoding other than UTF-8. In fact it could warn if the modeline  
> differs at all from the one shown in the Guide.

Hm, I would say this modeline is just a recommendation, and not 
mandatory. Port maintainers should be free to change it to their needs. 
If there were no changes allowed, setting a modeline in every file would 
be useless, you could just define it globally in your editor for Portfiles.

Most settings are not so important, only the encoding matters as we
expect every Portfile to be UTF-8.

Rainer