doc: Clarify %include search directory semantics

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
diff --git a/doc/changes.src b/doc/changes.src
index 7da6662..efed8a1 100644
--- a/doc/changes.src
+++ b/doc/changes.src
@@ -9,7 +9,7 @@
 
 \S{cl-2.14} Version 2.14
 
-\b Fixed \c{-I} option handling when ending slash is not present.
+\b Changed \c{-I} option semantics by adding a trailing path separator unconditionally.
 
 \b Fixed null dereference in corrupted invalid single line macros.