[syslinux] Thoughts: chaindev -> altchain

[Michal Soltys]

Hi

I was thniking about that chaindev branch I see slowly 
rotting in my git - and I was wondering: would it be 
acceptable to change it from "replace existing 
chain.c32" to "provide alternative altchain.c32" ? 
The rationale for such request:

- chaindev resides in its own directory under com32, 
  so there're no conflicts possible

- the dependency on disklib is trivial to solve - just 
  move disklib.{c,h} (which is de-facto used only by chain, 
  and consists of functions moved outside original 
  chain.c) to the chaindev subdir; any further swaps (e.g. 
  towards core disk functions) / backporting would be
  a trivial matter too

- the code would be easily available for others to 
  experiment with (use, patch, comment). I haven't had
  any problems presonally since my last commit, and
  it was tested pretty extensively

- the documentation is also included, though it needs
  some un-engrishing and a bit more friendliness