This functions are used in the whole code and are
mandatory for the python3 support to work. In python2
case nothing is touched.
* cmp_to_key:
converts a cmp= into a key= function
* decode_list:
decodes each element of a list. This is needed if
we have a mixed list with strings and bytes.
* decode_it:
Takes the input and checks if it is not a string.
Then it uses chardet to get the encoding.
