Added unicode constants class, and support for non-breaking spaces, which aren't preserved on save.

sample/sampleNovel/nwProject.nwx

@@ -1,5 +1,5 @@
 <?xml version='1.0' encoding='utf-8'?>
-<novelWriterXML appVersion="0.3.2" fileVersion="1.0" timeStamp="2019-10-28 21:42:26">
+<novelWriterXML appVersion="0.3.2" fileVersion="1.0" timeStamp="2019-10-29 11:29:39">
   <project>
     <name>Sample Project</name>
     <title>Sample Project</title>
@@ -11,7 +11,7 @@
     <spellCheck>True</spellCheck>
     <lastEdited>ba8a28a246524</lastEdited>
     <lastViewed>ba8a28a246524</lastViewed>
-    <lastWordCount>859</lastWordCount>
+    <lastWordCount>864</lastWordCount>
     <autoReplace>
       <A>B</A>
       <B>E</B>
@@ -103,10 +103,10 @@
       <status>Finished</status>
       <expanded>False</expanded>
       <layout>UNNUMBERED</layout>
-      <charCount>626</charCount>
-      <wordCount>101</wordCount>
-      <paraCount>3</paraCount>
-      <cursorPos>583</cursorPos>
+      <charCount>658</charCount>
+      <wordCount>106</wordCount>
+      <paraCount>4</paraCount>
+      <cursorPos>678</cursorPos>
     </item>
     <item handle="96b68994dfa3d" order="4" parent="e7ded148d6e4a">
       <name>A Note on Ipsums</name>