libpth transition

[Robert Millan]

Hi there!

We're going to do a little transition with libpth. I'm splitting libpthread
out of libpth into a separate package, which means all the packages that
depend on libpth2 need to be eventualy recompiled.

  NO, THIS IS NOT AN ABI BREAK. YOU DON'T HAVE TO REINSTALL YOUR SYSTEM.

The advantages are basicaly:

  libpth2 is no longer (de-facto) essential
  libpth-dev is no longer (de-facto) build-essential.

Which makes libpth non-disruptive, and allows for compiling those nasty
packages that Build-Conflict on libpth-dev. It also saves a few KBs in our
base tarball.

Isaac: The path is clear for libgcrypt now =)

Santiago et al: Please don't compile any version of pth. I announced intent
to NMU pth in archive, but even then I'm not adding Replaces:, so we shouldn't
have the patched binary untill we don't have any package that depend on
libpth2 (other than those actualy using libpth.so.*, of course).

-- 
Robert Millan

"[..] but the delight and pride of Aule is in the deed of making, and in the
thing made, and neither in possession nor in his own mastery; wherefore he
gives and hoards not, and is free from care, passing ever on to some new work."

 -- J.R.R.T., Ainulindale (Silmarillion)