0.002_02	2020-05-22	T. R. Wyant

    Refactor the get_*_grid() code. This has resulted in signature
    changes, though not (I believe) to anything that was in 0.002.

0.002_01	2020-05-15	T. R. Wyant
    Add methods get_active_text_grid(), get_used_text_grid(). Add
    bookkeeping of live cells in each row and column so the latter runs
    in linear time, not quadratic.

    Base grid on hash rather than array. This is faster on a large grid
    because I do not have to autovivify unused cells. Not surprisingly,
    the memory footprint is much smaller.

    Tweak change bookkeeping so that only one pass through the changes
    list is needed, not two.

0.002		2020-02-21	T. R. Wyant
    Increase Perl dependency to 5.8.1 and convert testing to Test2::V0.

    Eliminate redirections in POD URL links

0.001		2019-08-31	T. R. Wyant
    First production release.