[Laszlo-dev] try/catch

[P T Withington]

What do you think about at least permitting try/catch in swf for now,  
even if we just pass the try block through as a block, ignore any  
catch and pass through any finally.  It's lame, but it would let us  
unify a bunch of the LFC code base.

Then when we have time, we can actually implement the correct code  
generation for it...