Bump express from 4.15.4 to 4.16.4 (#128)

Bumps [express](https://github.com/expressjs/express) from 4.15.4 to 4.16.4.
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@4.15.4...4.16.4)

Signed-off-by: dependabot[bot] <support@dependabot.com>

package.json

@@ -7,7 +7,7 @@
   "author": "Ujjwal Sharma",
   "license": "GPL-3.0",
   "dependencies": {
-    "express": "^4.15.4",
+    "express": "^4.16.4",
     "github": "^11.0.0",
     "irc": "^0.5.2",
     "path": "^0.12.7",