TASKS

The load_files() function:
    - Find the files in a directory and read those files (Solved)
    - Fetch the files (Solved)
    - Index the files using Inverted Index (Solved)
    - Apply the Porter Stemming Algorithm to minimize the search words
    - Save the data structures for further use (Solved)
    - Make load_words_from_index() function load from all previously
loaded directories if the directory name wasn't given (Solved)

The search() function:
    - Process query string to BitArray operations;
Return the documents of the query (Solved)

The CLI (cmd module):
    - Let the user add new directories for loading (Solved)
    - List the loaded directories (Solved)
    - Check the integrity of the loaded directories
    - Read a query entered by the user and process it by showing the 
documents (the most important part) (Solved)

The GUI (wxPython):
    - Make all the CLI commands accessible through a GUI (Solved)

The testing:
    - Implement an exhaustive query search
    - Compare the results of query() from the results of the 
exhaustive search
    - Measure query evaluation time for big queries
    - Measure search time for big and/or numerous files