Update Waf for URL and specificity
@@ -1,4 +1,9 @@
-# for projects that use Waf for building: http://code.google.com/p/waf/
-.waf-*
-.waf3-*
-.lock-*
+# For projects that use the Waf build system: https://waf.io/
+# Dot-hidden on Unix-like systems
+.waf-*-*/
+.waf3-*-*/
+# Hidden directory on Windows (no dot)
+waf-*-*/
+waf3-*-*/
+# Lockfile
+.lock-waf_*_build