[shotwell] Use a Unicode apostrophe in a new string

[Piotr Drąg <piotrdrag src gnome org>]

commit 0db18fa08519427d6286ca5cba95aa11ca9f657f
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Sun May 6 18:36:54 2018 +0200

    Use a Unicode apostrophe in a new string
    
    See https://developer.gnome.org/hig/stable/typography.html
    
    https://bugzilla.gnome.org/show_bug.cgi?id=772339

 misc/org.yorba.shotwell.gschema.xml |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/misc/org.yorba.shotwell.gschema.xml b/misc/org.yorba.shotwell.gschema.xml
index b3f0c1b..bc03007 100644
--- a/misc/org.yorba.shotwell.gschema.xml
+++ b/misc/org.yorba.shotwell.gschema.xml
@@ -158,8 +158,8 @@
     
     <key name="use-dark-theme" type="b">
         <default>true</default>
-        <summary>prefer GTK's dark theme</summary>
-        <description>Whether to use the dark theme of GTK for Shotwell or not.</description>
+        <summary>prefer GTK+’s dark theme</summary>
+        <description>Whether to use the dark theme of GTK+ for Shotwell or not.</description>
     </key>
 
     <key name="transparent-background-type" type="s">