Removed a debug statement
Reduced the frequency of word group E
corrected the commandline for running the program
corrected some word mistakes
changed the last review time back down.
Added .backup files to gitignore
commented out the debug compile
Turned on optimization
Added a field for chapter. Not clear how this will be used, but we need to start dividing words into chapters for greater flexibility.
Trimmed off whitespace from the beginning and end of words
Changed the comparison to case insensitive when typing English words.
Added Korean.