Unit of length and 'Nautical miles/feet', rename 'Nautical miles'

[dmpr0]

Android task https://github.com/osmandapp/OsmAnd/issues/15724

ToDO

We need to add new Unit of length option to display Nautical miles with feet and rename current Nautical miles to Nautical miles/meters.

• [x] Rename Nautical miles to Nautical miles/meters
• [x] Add Nautical miles/feet

[Zirochkabila]

4.4.4.2 Done

[DmitrySvetlichny]

https://github.com/osmandapp/OsmAnd-iOS/pull/2461/commits