Add dependency on unsafe-coerce

Author: hdgarrood

bower.json

@@ -22,7 +22,8 @@
     "purescript-st": "^2.0.0",
     "purescript-tailrec": "^2.0.0",
     "purescript-tuples": "^3.0.0",
-    "purescript-unfoldable": "^2.0.0"
+    "purescript-unfoldable": "^2.0.0",
+    "purescript-unsafe-coerce": "^2.0.0"
   },
   "devDependencies": {
     "purescript-assert": "^2.0.0",