fixed broken link

Author: kimtg

README.md

@@ -45,7 +45,7 @@ OPTIONS:
 * [Syntax sugar](http://arclanguage.github.io/ref/evaluation.html) (`[]`, `~`, `.`, `!`, `:`)
 
 ## See also
-* [Arc Tutorial](http://tryarc.org/arc-tutorial/)
+* [Arc Tutorial](http://www.arclanguage.org/tut.txt)
 * [Arc Documentation](http://arclanguage.github.io/ref/index.html)
 * [Try Arc: Arc REPL In Your Web Browser](http://tryarc.org/)