[syslinux] isohybrid has 2 variants

[Ady]

> >What I reminder from it:
> >
> > The first "isohybrid" was in perl.
> > But that made perl a run-time dependency.
> >
> > A compiled version of "isohybrid" removed that
> > run-time dependency on perl.
> >
> >
> >What I think of it:
> >
> > The Perl variant of isohybrid should be removed
> > from the source tree.
> 
> One advantage of the Perl one for me is that I can run it on
> Windows. I had trouble with the binary one in Cygwin, but the Perl
> version worked well. 
> 
> --Ian

Although there are some "isohybrid.exe" around, there is no official 
support for them and they are also outdated.

The Syslinux mailing list already includes several emails about 
issues in the included isohybrid variants. I think that deleting 
either of them would be a mistake. At least users such as Ian might 
benefit from both being included.

Since both included variants are currently different, and both 
variants have problems, a user could either:
_ success with both; or,
_ success with one but fail with the other; or,
_ fail with both.

Additionally, a user could be using a different (not included in 
Syslinux) variant (specially when the included ones fail to 
accomplish the goal in some cases).

So when a common user reports about problems with isohybrid images, 
it is getting more difficult to know how exactly that image was 
generated, and therefore how to solve the problem; which means that 
potential improvements (fixes) are rare too.

Instead of deleting any of the isohybrid variants, I think it would 
be helpful to document the existence of _both_ of them. At least 
users would know that they might be able to try the second one when 
problems arise.

Ideally, the Perl variant should get updated at least with the 
patches that the C variant already includes, and then solve the 
remaining known problems. Any takers?

Regards,
Ady.