* user interface

- vario: fix overlapping text lines

* tracking

- SkyLines: update tracking IP address

* support for long-form `DTE` header in IGC files

* Windows

- fix buffer overflow causing crashes in the waypoint dialog

* Raspberry Pi

- support 64 bit kernels

- Raspberry Pi 4 support

- detect display dimensions and scale user interface accordingly

* macOS

- add macOS Catalina font path

for more see https://github.com/Turbo87/XCSoar-TE/blob/v6.8.15-TE/NEWS.txt#L55-L142