Added a readiness report and threshold

[catsdev]

Report readiness

Using the --readiness (-y) option will do two things:

• Create a readiness report by showing how many files contain spelling errors

        59 files with 0 errors
        5 files with at least 1 error
        1 files with at least 10 errors
        0 files with at least 50 errors
        0 files with at least 100 errors

        Readiness indicator: 90%

• Allow to pass a readiness threshold value which will determine if the tool throws an error or not. For example, passing a -y 90 would allow the current state of the files to pass the CI build without throwing an error (defaults to 100, no errors).