patches/diffs for full :browse! (fixes most of #1617)

[Simon Peyton-Jones]

| now, the bugs are identified and fixed, the things that should be
| done in other ways are left out, and the remaining patches look
| as simple as i hoped they'd be when i started this (so review

I took a look at your patch.  Indeed it now looks like a pretty modest, non-disruptive change to the code.  It's more than my life is worth to speculate about what might of might not be in 6.8.1 though!

Simon