Time to start keeping a NEWS file.

This covers changes made *after* the gsl-0.2 snapshot

* Changed libgsl_statisctics.a to libgslstatistics.a and
  libgsl_siman.a to libgslsiman.a, since most of the packages don't
  have the underscore.  Users will have to remove the old files,
  unless they do a "make uninstall" on the previous release before
  they install this new one.

* Changes to the random number suite

** Incorporated the gauss, poisson and exponential distributions in
   the standard libgslrandom.a
