hedgedoc: 1.7.0 -> 1.7.1 (fixes CVE-2020-26286 and CVE-2020-26287)

https://github.com/hedgedoc/hedgedoc/releases/tag/1.7.1
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-wcr3-xhv7-8gxc
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-g6w6-7xf9-m95p

pkgs/servers/web-apps/hedgedoc/package.json

@@ -1,6 +1,6 @@
 {
   "name": "HedgeDoc",
-  "version": "1.7.0",
+  "version": "1.7.1",
   "description": "The best platform to write and share markdown.",
   "main": "app.js",
   "license": "AGPL-3.0",
@@ -43,6 +43,7 @@
     "express": ">=4.14",
     "express-session": "^1.14.2",
     "file-saver": "^1.3.3",
+    "file-type": "^16.1.0",
     "flowchart.js": "^1.6.4",
     "fork-awesome": "^1.1.3",
     "formidable": "^1.0.17",
@@ -111,6 +112,7 @@
     "readline-sync": "^1.4.7",
     "request": "^2.88.0",
     "reveal.js": "^3.9.2",
+    "rimraf": "^3.0.2",
     "scrypt-async": "^2.0.1",
     "scrypt-kdf": "^2.0.1",
     "select2": "^3.5.2-browserify",