Restrict purescript version

Author: garyb

package.json

@@ -6,7 +6,7 @@
     "gulp-jscs": "^1.6.0",
     "gulp-jshint": "^1.11.2",
     "gulp-purescript": "^0.6.0",
-    "purescript": "^0.7.3-fixed",
+    "purescript": "0.7.3-fixed",
     "rimraf": "^2.4.1"
   }
 }