Documentation: redirectGitweb

Change-Id: Ia91d648bb2870bee41d12c381e6e9c549f4322a9

Documentation/config.md

diff --git a/Documentation/config.md b/Documentation/config.md
index dc7977d..8273617 100644
--- a/Documentation/config.md
+++ b/Documentation/config.md
@@ -20,6 +20,17 @@
 
 By default `allowOriginRegex` is unset, denying all cross-origin requests.
 
+### Gitweb redirector
+
+Redirect requests to old gitweb URLs after having migrated to Gitiles. Matching
+URLs will be redirected permanently to their Gitiles equivalent.
+Default: `true`.
+
+```
+[gitiles]
+redirectGitweb = false
+```
+
 ## Markdown
 
 ### Disabling markdown