Classify a captcha with its answer
classify_(cap, ans, path, rm_old, ...)The path to a captcha
Either NULL (for interactive classification) or
a string with the answer for the captcha
Where to save the renamed (answered) captcha file
(if NULL, will save file on the same folder as its unanswered
counterpart)
Whether or not to delete unanswered captcha after copying and renaming them
Other arguments passed on to read_captcha()