[Simh] Unix 1st edition support

[Bob Supnik]

This is really great work, and I'm delighted to see it progress.

I've reviewed the current KE11A implementation, and it will require some 
changes before it can be generally released.  Specifically,

1. divide overflow is not handled correctly
2. left shifts of 32 need to be special cased, because in C, (32b 
quantity << 32) is undefined (and it works differently on different 
machines)
3. normalize is not setting the CC's

and a bunch of other nits.

I'll include the KE11A in the next release of SimH.  If anyone has test 
code (or better still, the diagnostics with documentation), please let 
me know.

I agree also that a real DC11 is needed, and I'd like to get that into 
the next release as well.

/Bob Supnik