Effects V2, new BlindDown effect

This functionality has been requested by some of you, so here it is:

Effect.BlindDown()—smoothly reveals an element by changing its height from 0 to whetever the full element measures. The element is NOT required to have a fixed height defined. It also works somewhat with tbody elements on tables (at least it does in Firefox).

But have a look at the Effects V2 demo page to see what this all amounts to.

Note that the name will probably change when it’s finished—if you have suggestions for new names for .Blind() and .BlindDown(), feel free to post a comment…