disable hide account feature for accounts not managed through emerald (ie geth accounts)

[whilei]

For accounts not managed through the Emerald backend, the hide feature should be disabled (visible, but greyed-out) instead of just absent.

[gagarin55]

We disable hide only for non-zero balances, but anyway let's show disabled hide button

[splix]

Hide/remove is disabled for accounts with a balance to avoid losing PK for account with money. For ledger it's not an issue, as PK is stored in HW key anyway, just matter of displaying it with other accounts. I think it should be possible to remove Ledger backed accounts

[shanejonas]

I don't think we show geth accounts, just ones you've imported yourself, but we are now showing hide in a disabled state in the UI for clarity