NEWS: prepare for 6.6.5
Engine/Task/ObservationZones: BGAStartSectorZone: Change from KeyholeZone to SymmetricSectorZone

A BGAStartSectorZone has no keyhole.
LibPNG.cpp: Added missing header for memcpy.
kobo/inittab: don't present root terminal on serial port

Serial port may be used for GPS.
kobo/rcS: disable flashing LED on startup
doc: document Kobo Mini installation
po: update xcsoar.pot and *.po
Add Key code constants for Android
InputConfig: use constexpr instead of enum
Util/CharUtil: relicense to BSD-2
kobo/rcS: don't check for XCSoarData

This prevented new XCSoar users with a fresh Kobo from seeing the
KoboMenu.  I don't know why I wrote this check, it was bogus.  If
XCSoar has never been run before, and the user hasn't explicitly
created XCSoarData, he will not be able to run XCSoar for the first
time.  Duh.
Thread/Handle: add "pure" attribute
Thread/Handle: add API documentation for GetCurrent()
po: update Finnish translation
po: update Polish translation
build/kobo.mk: Include italic font variants
Screen/*: Load "real" italic font variants if they exist
Merge branch 'master' of git://git.xcsoar.org/xcsoar/apf/xcsoar
RowFormWidget: AddButton() returns WndButton pointer
KoboMenu: change window title