void load istream &inputfile, To_Do_Item_Ptr &head

This function reads the given to-do list from inputfile and creates a linked list in memory by adding the to-do items in the file to the end of the list. The input stream must be successfully opened by the caller. head is an output parameter and its incoming value should be NULL but could be undefined. Its outgoing value should either be NULL or a reference to the first node of the list that has been created