README: change code.google.com link to GitHub

Signed-off-by: David Symonds <[email protected]>

README

@@ -5,7 +5,7 @@ Leveled execution logs for Go.
 
 This is an efficient pure Go implementation of leveled logs in the
 manner of the open source C++ package
-	http://code.google.com/p/google-glog
+	https://github.com/google/glog
 
 By binding methods to booleans it is possible to use the log package
 without paying the expense of evaluating the arguments to the log.