Update build from master.

boost-commitbot · boost-commitbot · commit 13f1549597d3 · 2015-08-11T10:00:14.000-04:00
diff --git a/tools/build b/tools/build
@@ -1 +1 @@
-Subproject commit cbddcde5953c8e51f52bfe612f53d0b779ade5f3
+Subproject commit 494e05169913257f23e4ea30eb55338853c094b1
