Word wrap button labels on soft hypens

If the UTF-8 sequence for the Unicode Soft Hyphen ("Non-printable U+00AD")
occurs in the text to be used as the label of a button, and the label
is still too wide after any wrapping done based on either space and/or a
visible hyphen ("-", U+002D), a visible hyphen will be introduced and
the label will be wrapped.

e.g. Norwegian Nynorsk "Regnbogesyklus"

Regnboge-
syklus

(rather than all crammed on one line and impossible to read)

h/t Karl for the idea.

Closes https://sourceforge.net/p/tuxpaint/bugs/288/

src/org.tuxpaint.Tuxpaint.appdata.xml.in

@@ -47,7 +47,7 @@
     </screenshot>
   </screenshots>
   <releases>
-    <release version="0.9.33" date="2024-05-19">
+    <release version="0.9.33" date="2024-06-01">
       <description>
         <p>Transparent Erasers.</p>
         <p>Brushes support descriptions.</p>
@@ -55,6 +55,7 @@
         <p>Updated Magic tools: 3D Glasses (now offers different anaglyph color combinations).</p>
         <p>Magic tools may be ungrouped ("ungroupmagictools").</p>
         <p>Localization updates.</p>
+        <p>Improved word wrapping in buttons (via hyphens and soft hyphens).</p>
       </description>
     </release>
     <release version="0.9.32" date="2024-01-28">