FileManager: Remove top submenu to open special folders, load storage overview in filemanager instead

[gsantner]

• Remove top menu submenu to open special folders, go to virtual storage directory folder instead
• There all special folders/devices/lists are available too, and only needs to be maintained at one location then
• this way less duplication of those options, and all of them are available outside mainactivity too

[harshad1]

This is nice. Makes navigation cleaner imo.

Should we also remove long press fab to jump folders?

[gsantner]

Would make that jump to storage too, instead of the current target