Updating broken-TODO.

Dan Ibanez pushed some changes to SCOREC/core new_stk that seem to fix the
Exodus write bug. I write "seem to" because I've tested the mods only on our
small test problems. In particular, in Heat3DFMDB/input.xml, I changed the .vtk
file extension to .exo. I did this in the tpetra and merge branches. Then I used
exodiff on the two sets of four files. I get the message "exodiff: Files are the
same" for all four.

Thanks Dan!