Modularization

The idea is to convert the different Perl scripts into Perl modules.

With this change Ninka can be used as a Perl module from inside Perl. It could also be packaged and be released as a CPAN module. I added perldoc to every module.

Usage:

    use Ninka;

    my $input_file = 'some/path/file_of_interest';
    my $verbose = 0;

    my $license_result = Ninka::process_file($input_file, $verbose);

There is no need for the intermediate files with this implementation - so I removed them. If they are required (e.g. to help debugging when adding new licenses), they could be easily generated again.