Revert "lib.xcsoar_.flightpath: don't set threshold to zero"

This reverts commit 9e72812d8df3fec37ba7327d4460efeee9ccefbd.

This seems not to be the real cause and introduces other side-effects.
Needs some further investigation, but reverted for now.
wingman-table.jinja: fix pilot's name and show co-pilot too, if available
wingman-table.jinja: show aircraft model in aircraft column

Add CN and Reg if available
wingman-table.jinja: add schema.org itemtype to table
templates/flights: enable tooltips