Merge pull request #14 from unbalancedparentheses/master

New stuff from @unbalancedparentheses
Update README.md
[#16] Added parsing code form elvis_code.
Merge pull request #17 from inaka/jfacorro.16.move.elvis_code.to.ktn_code

[Closes #16] Added parsing code form elvis_code
added user default
added eper
Resolves bugs: out of bounds 

Resolves bugs: out of bounds if random length is bigger than the number of allowed chars