update slang to 2.0?

[Bill Nottingham]

Bill Nottingham (notting at redhat.com) said: 
> In Core:
> newt
> slrn
> crypto-utils
> timidity++
> system-config-securitylevel
> mc
> 
> In Extras:
> caca
> aalib
> most
> jed

AFAIK, of these, the ones that might require more than just a
trivial rebuild:

- newt (requires a trivial patch for a couple of box drawing/arrows,
  I have this)
- slrn, jed (requires a new developmnet version)
- most (requires a new released version)
- mc (didn't investigate too much. Of course, this could probably
  be built against ncurses :) )

Bill