[GraphicsMagick/f20] (8 commits) ...handle upgrade path for introduction of -doc subpkg in 1.3.19-4

[Rex Dieter]

Summary of changes:

  5ed0906... trim changelog (*)
  d4472c3... 1.3.19 (#1047676) (*)
  e8b1410... BR: jbigkit, libwebp, xdg-utils, xz (*)
  1c448fc... ppc64le is a multilib arch (#1051208) (*)
  8d170c8... Split docs into -doc subpackage, drop README.txt (#1056306) (*)
  f26a1c1... upstream patch, drop debug output (#1060665) (*)
  be42bd8... forgot to bump release (*)
  b25db47... handle upgrade path for introduction of -doc subpkg in 1.3. (*)

(*) This commit already existed in another branch; no separate mail sent