Ordered list with proper counting.

Author: isoos

app/lib/shared/changelog.dart

@@ -238,7 +238,8 @@ class _MarkdownVisitor extends dom_parsing.TreeVisitor {
         final indent = '  ' * (_listDepth - 1);
         _write(indent);
         if (parent == 'ol') {
-          _write('1. ');
+          final childIndex = (node.parent?.children.indexOf(node) ?? 0) + 1;
+          _write('$childIndex. ');
         } else {
           _write('- ');
         }

app/test/shared/changelog_test.dart

@@ -583,7 +583,7 @@ And:
           'And:\n'
           '\n'
           '1. order\n'
-          '1. list\n'
+          '2. list\n'
           '\n'
           '> With multiline quoted `code`and *text*.\n'
           '\n'