Slightly optimize maxZeroes in ArithmeticCoder.
Use xor instead of subtraction to make sure that you don't miss any possible zeroes.
Add comments to ArithmeticCoder's encode.
Add comments to ArithmeticCoder's decode().
Add Javadocs for methods in ArithmeticCoder.
Write Javadocs for the Coder interface.
Add Javadocs to FileReader and FileWriter.
Add and fix Javadocs for CharMap.
Add comments to FileReader, FileWriter, MainWindow
Add comments to SummaryWindow.
Remove unnecessary util classes.
Fix directory checking.
Merge branch 'comments'
Remove unnecessary stuff in HuffmanCode.