Internal Application errors on 0.9.3

[William Shipley]

Apparently most of these errors are caused by HTML that goes too many  
levels deep, which causes nested RTF.  It turns out the NeXT text object  
only allows like 20 levels of nested RTF, then it raises an exception.   
Thank you!

We're fixing this by making incompatible tags automatically close old tags.  
 (For example, starting an <h2> will close off the previous <h1> even if  
you forgot to.)  This should cover most of the errors, and will also fix the  
ever-growing (or shrinking) problem people have with these non-compliant  
pages.

-Wil