fix: .snyk & package.json to reduce vulnerabilities

The following vulnerabilities are fixed with a Snyk patch:
- https://snyk.io/vuln/npm:extend:20180424
- https://snyk.io/vuln/npm:stringstream:20180511

.snyk

@@ -0,0 +1,11 @@
+# Snyk (https://snyk.io) policy file, patches or ignores known vulnerabilities.
+version: v1.13.5
+ignore: {}
+# patches apply the minimum changes required to fix a vulnerability
+patch:
+  'npm:extend:20180424':
+    - electron > electron-download > nugget > request > extend:
+        patched: '2019-06-13T13:35:14.273Z'
+  'npm:stringstream:20180511':
+    - electron > electron-download > nugget > request > stringstream:
+        patched: '2019-06-13T13:35:14.273Z'

package.json

@@ -22,7 +22,9 @@
     "gifify": "gifify -p 405:299 -r 5@3 Untitled.mov-00.00.00.971-00.00.19.780.mp4",
     "lint": "eslint --ext .jsx --ext .js .",
     "clean": "rm -rf dist ffmpeg-tmp/extracted ffmpeg-tmp/binaries package",
-    "clean-ffmpeg": "rm -rf ffmpeg-tmp/archives"
+    "clean-ffmpeg": "rm -rf ffmpeg-tmp/archives",
+    "snyk-protect": "snyk protect",
+    "prepublish": "npm run snyk-protect"
   },
   "author": {
     "name": "Mikael Finstad",
@@ -78,6 +80,8 @@
     "sweetalert2-react-content": "^1.0.1",
     "trash": "^4.3.0",
     "uuid": "^3.3.2",
-    "which": "^1.2.11"
-  }
+    "which": "^1.2.11",
+    "snyk": "^1.177.1"
+  },
+  "snyk": true
 }