Fix path expression documentation about '*' and '**'

'*' matches any string that does not include slashes while '**' matches
any string, including slashes.

Change I1ddc8bf32 was changing this, but this got reverted by change
I049316068. But the revert forgot to update this piece of the
documentation.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I76373da557d0ced07408cd5aa499424671b4c14c
diff --git a/resources/Documentation/path-expressions.md b/resources/Documentation/path-expressions.md
index e5c2dd8..69a27c1 100644
--- a/resources/Documentation/path-expressions.md
+++ b/resources/Documentation/path-expressions.md
@@ -18,7 +18,8 @@
 
 Globs support the following wildcards:
 
-* `*`: matches any string, including slashes
+* `*`: matches any string that does not include slashes
+* `**`: matches any string, including slashes
 * `?`: matches any character
 * `[abc]`: matches one character given in the bracket
 * `[a-c]`: matches one character from the range given in the bracket