Allow directories to be specified with the --input option.

Previously directories were specified with the -l --logdir option.
This was removed and now directories included with the -i option will be
traversed and any files who's names end in '.log' will be processed.
This is accomplished by simply adding them to the list of input files.
Merge pull request #4 from alexKleider/feature/allow_dirs

Allow directories to be specified with the --input option.