locking versions (#113)

Author: Nithin Krishna

package.json

@@ -31,11 +31,11 @@
     ]
   },
   "dependencies": {
-    "app-root-path": "~2.1.0",
+    "app-root-path": "2.1.0",
     "frg-ethereum-runners": "https://github.com/ampleforth/frg-ethereum-runners.git#v1.0.0-alpha",
     "js-yaml": "^3.13.0",
-    "openzeppelin-eth": "~2.0.2",
-    "truffle": "~4.1.14"
+    "openzeppelin-eth": "2.0.2",
+    "truffle": "4.1.14"
   },
   "devDependencies": {
     "chai": "^4.1.2",