[Kst] [Kst-plot/kst] a9d24f: GSL-2.x support.

[D. V. Wiebe]

  Branch: refs/heads/master
  Home:   https://github.com/Kst-plot/kst
  Commit: a9d24f91057441bbd2e3ed9e7536b071121526cb
      https://github.com/Kst-plot/kst/commit/a9d24f91057441bbd2e3ed9e7536b071121526cb
  Author: D. V. Wiebe <dvw at ketiltrout.net>
  Date:   2016-03-10 (Thu, 10 Mar 2016)

  Changed paths:
    M src/plugins/fits/non_linear.h
    M src/plugins/fits/non_linear_weighted.h

  Log Message:
  -----------
  GSL-2.x support.