chore(package): update electron-builder to version 20.6.2

Closes #26

Author: greenkeeper[bot]

package.json

@@ -61,7 +61,7 @@
   "devDependencies": {
     "devtron": "1.1.X",
     "electron": "~1.7.5",
-    "electron-builder": "^19.6.1",
+    "electron-builder": "^20.6.2",
     "electron-rebuild": "~1.7.0",
     "xo": "0.18.X"
   },