Fix bug with latin characters and ignore usernames optional

Not sure if you agree with them, but I added some changes to my fork that maybe are useful for you, if not, please ignore my pull request:

- I've added a new option to optionally ignore all the usernames mentioned by an user. Sometimes the usernames are not useful in a wordlist.
- To support non English tweets, I've added some code to avoid splitting words with accents or cyrillic characters into two words with nos sense (text.gsub!(/[^\w \s \d]/, ' ')), but instead transform to a word without the "offending" character.
- Added new folder (ignore) to ignore special words non meaningful or useful to the objective of this script. This is a TODO feature.