NoteEdit: Configure textCapitalization settings

Without this writing a journal is a pain as the first letter is not
automatically capitalized.

lib/note_editor.dart

@@ -67,6 +67,7 @@ class NoteEditorState extends State<NoteEditor> {
           border: InputBorder.none,
         ),
         controller: _textController,
+        textCapitalization: TextCapitalization.sentences,
       ),
     );