ouch, fixed nasty month-old storage listener bug

Today I noticed that /misc/stor-demo.html only worked a quarter of the
time. Then I checked two-window editing in /vorp/edit and that was
broken too! Though I was going crazy!
But then
http://stackoverflow.com/questions/1520800/why-regexp-with-global-flag-i
n-javascript-give-wrong-results
'Cause I changed stor to use a static regexp object a month ago and
didn't test multi-window storage manipulation. Eep.