Updated logs viewer component

- now by default last 50 lines are showed
- added copy to clipboard button
- added loading spinner to indicate to users when the logs are loading

app.get('/api/logs') is now app.post to allow for additional parameters (such as lines to retrieve)

backend/package.json

@@ -50,6 +50,7 @@
     "passport-jwt": "^4.0.0",
     "passport-local": "^1.0.0",
     "progress": "^2.0.3",
+    "read-last-lines": "^1.7.2",
     "shortid": "^2.2.15",
     "unzipper": "^0.10.10",
     "uuidv4": "^6.0.6",