[gegl] docs/features: fix some broken links to op browser

[Øyvind Kolås <ok src gnome org>]

commit 87d78fa8ba3b3e929b9f3f3af3fdb6033cfaea89
Author: Øyvind Kolås <pippin gimp org>
Date:   Sun Mar 13 15:27:20 2016 +0100

    docs/features: fix some broken links to op browser

 docs/features.txt |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/docs/features.txt b/docs/features.txt
index bcbcd85..ebfb188 100644
--- a/docs/features.txt
+++ b/docs/features.txt
@@ -24,13 +24,13 @@ GEGL Feature List
        to use them through the GeglBuffer API).
   - Operations
       * PNG, JPEG, SVG, EXR, RAW, ffmpeg, v4l and other image sources.
-      * link:operations.html#cat_render[Pattern renderers]
-      * link:operations.html#cat_math[Arithmetic operations]
-      * link:operations.html#cat_porter-duff[porter duff compositing]
+      * link:operations.html#category%20render[Pattern renderers]
+      * link:operations.html#category%20math[Arithmetic operations]
+      * link:operations.html#category%20porter-duff[porter duff compositing]
       * SVG filter modes and full set of compositing ops from SVG-1.2 draft.
       * Gaussian blur, bilateral-filter, symmetric nearest neighbour, linear
       * blur, unsharp mask, pixelize and more.
-      * link:operations.html#cat_color[Color correction].
+      * link:operations.html#category%20color[Color correction].
       * Text rendering using cairo and http://pango.org/[pango].
       * HDR exposure merging and tone mapping operations.
       * Most operations operate in