set precise ssh2 version

Author: lenchvolodymyr

package.json

@@ -25,7 +25,7 @@
   "dependencies": {
     "debug": "2.6.9",
     "lodash.defaults": "^4.1.0",
-    "ssh2": "^1.4.0"
+    "ssh2": "1.4.0"
   },
   "devDependencies": {
     "chai": "3.5.0",