Expect locations to have an index and that's it.

This row, column stuff doesn't bring enough advantage to be worth the complexity
involved in using it.
Replace line, col with index.
Have Fingerprinter return only an index.
Remove leftover temporary file.
Test for a PlaintextPreprocessor.
Add a working plaintext preprocessor.
Test for a source code preprocessor.
Shorten the names of preprocessors.
Have Fingerprinter use preprocessors.

By default, Plaintext is used.
Add rouge as a dependency.