The attached patch has been applied into svn r747. It adds the options 'dump',
'dump-noversion' and 'dump-tofile' to commands 'install', 'upgrade', and 'remove'. 

Option 'dump-tofile' requires either 'dump' or 'dump-noversion' to be specified.
When dumping without 'dump-tofile', output goes to stderr.

If asked for dump, the transaction won't commit.