Cloudron 3.5.4 released

[girish]

We pushed out a patch release to 3.5 with many fixes:

• Make reboot required check server side
• Update node to 10.15.1
• Enable gzip compression for large objects
• Update docker to 18.09
• Add UI to copy app's backup id
• Block platform updates based on app manifest constraints
• Make crash logs viewable via the dashboard
• Fix issue where uploading of filenames with brackets and plus was not working
• Add notification for cert renewal and backup failures
• Fix issue where mail container was not updated with the latest certificate