* mh/string-list:
api-string-list.txt: initialize the string_list the easy way
string_list: add a function string_list_longest_prefix()
string_list: add a new function, string_list_remove_duplicates()
string_list: add a new function, filter_string_list()
string_list: add two new functions for splitting strings
string_list: add function string_list_append_nodup()