[gimp] Update NEWS

[Alexandre Prokoudine <aprokoudine src gnome org>]

commit ec014083591d44f400c99bc9a2068ab51b8dafd6
Author: Alexandre Prokoudine <alexandre prokoudine gmail com>
Date:   Wed Jun 7 22:49:09 2017 +0300

    Update NEWS

 NEWS |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index b775cf0..b9751f8 100644
--- a/NEWS
+++ b/NEWS
@@ -85,6 +85,7 @@ GUI and usability:
     correct color inversion.
   - Quit dialog now exits when all the images in the list have been
     saved.
+  - The built-in error dialog now displays errors outputted by GEGL.
 
 Color selection and management:
 
@@ -114,7 +115,10 @@ Configurability:
 
 Tools:
 
-  - Add Hue-Chroma operation/tool.
+  - Add Hue-Chroma operation/tool that operates in CIE LCH color space.
+  - Replace Color Balance and Hue-Saturation with GEGL-based filters with
+    a custom user interface to ease future transition to non-destructive
+    editing planned for v3.2.
   - The Move tool now shows relative coordinates when moving guides
     and sample points.
   - The Measure tool has better digit precision now (before that, at