Change tax day from 4/15 out of respect for Boston victims.

If 9/11 had happened on 4/15 instead, "tax day" would have been changed by now. It doesn't matter if it is changed to a date before or after 4/15; there will always be people who wait until the last minute anyway. 4/1 might be apropos. Some folks might find humor in it if it were 4/20. April 30 also makes sense.
Let's change it from April 15th, the events in Boston on that day were taxing enough.