%>%                     re-export magrittr pipe operator
Crossword               Crossword
cw_greplv               a vectorized version of grep
cw_matrix_to_df         function that turn matrix into a data.frame in
                        long format
cw_normalize_words      normalize words to be added to grid
cw_to_json              function implementing to_json method
cw_wordlist_animal_en   en - animals
