Purescript to 12 in package.json

Author: AlexMouton

package.json

@@ -8,7 +8,7 @@
     "eslint": "^3.17.1",
     "pulp": "^11.0.0",
     "purescript-psa": "^0.5.0",
-    "purescript": "^0.11.1",
+    "purescript": "^0.12.0",
     "rimraf": "^2.5.4"
   }
 }