[18163] commited by me yesterday (and reverted in [18165]) was

[18163] commited by me yesterday (and reverted in [18165]) was
broken. I didn't restart rails when testing it because I thought lib/
was auto-refreshed as well and that:

    ruby -e 'x = []; x[0]["foo"] = "bar"'

Would work and autovify like it does in Perl. But no, you have to do:

    ruby -e 'x = [{}]; x[0]["foo"] = "bar"'

This commit is equivalent to [18163] aside from that fix to lib/potlatch.rb