[shotwell] Re-word "Width or Height" scaling constraint

[Jens Georg <jensgeorg src gnome org>]

commit ca488db5886936aafe4f1b3590489d1a16650fa1
Author: Jens Georg <mail jensge org>
Date:   Mon Sep 25 21:59:03 2017 +0200

    Re-word "Width or Height" scaling constraint
    
    Also add some documentation on what that is supposed to do
    
    https://bugzilla.gnome.org/show_bug.cgi?id=787553

 help/C/share-export.page |    9 ++++++++-
 src/Dimensions.vala      |    2 +-
 2 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/help/C/share-export.page b/help/C/share-export.page
index 992ca11..693a52a 100644
--- a/help/C/share-export.page
+++ b/help/C/share-export.page
@@ -35,7 +35,14 @@ Shotwell will be included, and Shotwell will convert photos to the destination f
 </list>
 </item>
 <item><p>The image quality for exporting (Low, Medium, High, or Maximum).</p></item>
-<item><p>A scaling constraint (which means how Shotwell will decide to scale the photos down), and the 
desired pixel size.</p></item>
+<item><p>A scaling constraint (which means how Shotwell will decide to scale the photos down), and the 
desired pixel size.</p>
+<terms>
+<item><title>Original size</title><p>Image will be exported without any scaling applied</p></item>
+<item><title>Longest edge</title><p>Image will be exported by having its longest edge scaled to 
<gui>Pixels</gui> and the other according to the aspect ratio</p></item>
+<item><title>Width</title><p>The image width will have its width scaled to the given pixel size and its 
height according to the aspect ratio. This is equivalent to <gui>Longest Edge</gui> for landscape 
pictures.</p></item>
+<item><title>Height</title><p>The image height will have its height scaled to the given pixel size and its 
width according to the aspect ratio. This is equivalent to <gui>Longest Edge</gui> for portrait 
pictures.</p></item>
+</terms>
+</item>
 <item><p>The option whether you like to export metadatas such as tags or ratings. This can help to save your 
privacy if you have geolocation tags or tags which shouldn't be seen by anyone.</p></item>
 </list>
 
diff --git a/src/Dimensions.vala b/src/Dimensions.vala
index 7c9eed6..99fe469 100644
--- a/src/Dimensions.vala
+++ b/src/Dimensions.vala
@@ -17,7 +17,7 @@ public enum ScaleConstraint {
                 return _("Original size");
                 
             case DIMENSIONS:
-                return _("Width or height");
+                return _("Longest edge");
             
             case WIDTH:
                 return _("Width");