Update runtime files.
Add missing test files.
diff --git a/runtime/doc/usr_28.txt b/runtime/doc/usr_28.txt
index 8a02838..ea65416 100644
--- a/runtime/doc/usr_28.txt
+++ b/runtime/doc/usr_28.txt
@@ -18,7 +18,7 @@
 |28.7|	Folding by syntax
 |28.8|	Folding by expression
 |28.9|	Folding unchanged lines
-|28.10| Which fold method to use?
+|28.10|	Which fold method to use?
 
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