SVK::MimeDetect - interface for MIME type detection algorithms

This defines an interface for MIME type detection algorithms. A MIME type detection module doesn't need to inherit from this module, but it does need to provide the same interface. See INTERFACE for details.

new should return a new object which implements the checktype_filename method described below. The default implementation simply returns an empty, blessed hash.

Given a single, absolute filename as an argument, this method should return a scalar with the MIME type of the file or undef if there is an error.