po: update xcsoar.pot
Tracking/SkyLines: use uint32_t instead of unsigned for the id

Be explicit about the required integer size.
Dialogs/TrafficList: move code to OpenDetails()
Dialogs/TrafficList: show SkyLines traffic
Dialogs/TrafficList: check IsFlarm() in UpdateVolatile()
Dialogs/TrafficList: clear record/callsign on SkyLines traffic

Fixes crash.
Dialogs/TrafficList: add per-item "location" attribute

Show vector to SkyLines traffic.
german manual: corrections to chapter 8.added pictures for easy access master-slave modei, updated buttons.
Manual de/ch13_history.tex: Mostly typos and corrections.