Update utf8proc dependency to v2.1

philipturnbull · philipturnbull · commit 8a15da90fb08 · 2017-06-21T09:55:13.000-04:00
This includes JuliaStrings/utf8proc#66 which is an out-of-bounds read when parsing malformed utf8 characters.
diff --git a/externals/utf8proc b/externals/utf8proc
@@ -1 +1 @@
-Subproject commit ec0daa50bbedc36a0bada4a0f713eb9dc317d444
+Subproject commit 40e605959eb5cb90b2587fa88e3b661558fbc55a
