Disk - Enable trim support

[niemyjski]

I was reading over the docs to figure out how to add a legacy disk instead of SSD type.. I noticed that you can enable trim support (would be good for attached ssd's???). Looks like we are currently setting nodiscard

https://docs.microsoft.com/en-us/azure/virtual-machines/virtual-machines-linux-classic-attach-disk

[Mpdreamz]

we typically recommend nodiscard over continuous trimming with discard and doing a periodic trim through fstrim see also:

https://www.elastic.co/blog/is-your-elasticsearch-trimmed

That said we should look into automatically creating a daily trim job/service.