Point to skiadocs in our README.

This seems to be the canonical location for all skia documentation
nowadays.

R=epoger@google.com

Review URL: https://codereview.chromium.org/276483008

git-svn-id: http://skia.googlecode.com/svn/trunk@14663 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/README b/README
index 84e4ecc..a60bca6 100644
--- a/README
+++ b/README
@@ -1,3 +1,3 @@
 Skia is a complete 2D graphic library for drawing Text, Geometries, and Images.
 
-See full details, and build instructions, at http://code.google.com/p/skia/wiki/DocRoot
+See full details, and build instructions, at https://sites.google.com/site/skiadocs/home