🚀 Feature: Diskpace info/warnings for admin and user

[GitNees]

🔖 Feature description

Gui shows detailed diskpace info when admin logged in
Basic diskpace left info for users when logged in (next to upload button?)

🎤 Pitch

*Keep eye on diskspace used realtime, so you quicker see if there soon will need to be an action taken
*Send email to admin after certain amount of diskspace is used, for example to set a value in percentage
*Show users only free diskpace, also in case they try to upload a larger file then space is left and give a warning popup, that its not currently possible.