remove deps of the release tool

package.json

@@ -25,22 +25,11 @@
     "superagent": "^0.21.0"
   },
   "devDependencies": {
-    "aws-sdk": "^2.1.10",
-    "colors": "^1.0.3",
-    "commander": "^2.6.0",
-    "easy-table": "^0.3.0",
     "expect.js": "^0.3.1",
     "istanbul": "^0.3.5",
     "lodash": "^3.2.0",
     "mocha": "^2.1.0",
-    "nock": "^0.59.1",
-    "postmark": "^1.0.0",
-    "readline-sync": "^0.8.0",
-    "semver": "^4.3.0",
-    "ssh2": "^0.4.6",
-    "supererror": "^0.6.0",
-    "underscore": "^1.8.3",
-    "yesno": "0.0.1"
+    "nock": "^0.59.1"
   },
   "scripts": {
     "test": "NODE_ENV=test ./node_modules/istanbul/lib/cli.js test $1 ./node_modules/mocha/bin/_mocha -- -R spec ./src/test",