V3 fixes for classes.exp

[Jim Blandy]

Michael Snyder <msnyder@cygnus.com> writes:
> Jim, this patch extends what you did for "ptype class A" back in April
> to a bunch of other classes.  I thought you and Michael C. might review
> it, since you've both worked so hard on the V3 testing issues.  
> The changes:
> 
>   * Make the whitespace optional in "const &"
>   * Make the "void" optional in constructors with no params
>   * Make the private decl. of the vtable member optional
> 
> Also recognize a few additional constructors that were not
> around before.  This does not address the issue of multiple
> constructors with the same apparent type.

Thanks!

We know that GDB is printing bogus constructor info at the moment.  I
don't think the tests should be changed to match the constructors GDB
currently prints.  (I'm sorry --- I assume those changes probably took
the bulk of your time!)

The rest of it looks great.