Barrier opening

[Nick-Tallguy]

Draft - ToDo

Requires a new icon - currently using icon from cycleway width,

https://github.com/streetcomplete/StreetComplete/issues/5678 refers

Have tested with emulator on Android Studio, and have apk installed on my phone (Google pixel 8A).

This changeset by me on barrier = entrance.

First attempt at anything to do with kotlin or Android, so please check carefully & please let me know if there is anything I can do to improve - would like to contribute more in the future.