[gegl] Update NEWS

[Alexandre Prokoudine <aprokoudine src gnome org>]

commit e98f33c377ec2f3afda9548188443b333357e421
Author: Alexandre Prokoudine <alexandre prokoudine gmail com>
Date:   Sat Sep 29 17:19:17 2018 +0300

    Update NEWS

 docs/NEWS.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/docs/NEWS.txt b/docs/NEWS.txt
index 333d18a40..43a5f6d99 100644
--- a/docs/NEWS.txt
+++ b/docs/NEWS.txt
@@ -22,7 +22,8 @@ gif-load: new operation for decoding GIF images/animations, with frame delay
 exposed as an out-property.
 
 exr-save: do not hard-code a version name space
-long-shadow: add mipoint parameter
+long-shadow: add 'Fading (fixed length)' style with a new user-defined
+'Midpoint' parameter
 
 Updated all operations to use new iterator API