Migration to VueJs and more

[Sebclem]

I'm currently migrating the addon to VueJs + Typescript, this will make the app more easy to maintain and i'm also planning to add some unit/e2e test.

With this migration I will also implement some long wanted features. This issue is here to track my progress.

Features:

• [ ] Multiple cron #88
• [ ] Chunked upload (This will prevent 413 errors #9)
• [ ] Home assistant status entity #1
• [x] Partial / Full backup support #63
• [x] Custom Webdav endpoint #108 #89
• [ ] Auto empty trashbin #103
• [x] Rebuild status
• [ ] Tests

UI:

• [x] Event viewer
• [x] Status viewer
• [x] Cloud config
• [x] Backup config
• [x] Backup viewer HA
• [x] Backup viewer Cloud

Bug:

• [ ] Invalid password cause brute force security to trigger (webdav)
• [ ] Performance issue when message list is getting big