[applets/batterymonitor] BatteryItem: Move battery details and charge threshold hint

They were supposed to be in the column on the right this whole time, as
was indicated by an artificial Layout.leftMargin (ex-anchors.leftMargin).

Cons: Now the ToolTip pops up anywhere over a possibly lengthy details
and inhibition hint's text.

Pros: The ToolTip is never active.