Dialogs/Waypoint/WaypointInfoWidget: Check date_available before calculating sunrise and sunset
ThermalAssistantLook: Consider InfoBox inverse setting when rendering as Gauge

Fixes trac issue #2702.
IO/BatchTextWriter: remove unused WriteLine(TCHAR*) overload
IO/BatchTextWriter: include cleanup
IGCWriter: smaller buffers
NMEALogger: make local symbols "static"
test/WriteProfile*: remove obsolete programs
Util/StaticString: add method SetUTF8()
Profile: use narrow strings by default

Convert from UTF-8 to TCHAR only when needed.  This reduces overhead
on Windows.
test/...: use OS/Args.hpp
test/*: use WideToUTF8Converter instead of NarrowPathName
test/RunDialog: use _ftprintf() instead of NarrowPathName
OS/PathName: move classes to ConvertPathName.hpp

Reduce header dependencies.
Driver/IMI: make constants "const"
*: use more constexpr
Makefile: add new target "KOBO"

For Kobo Mini and others.  It compiles, but SDL doesn't work yet.
TaskAdvance: use references instead of pointers
TaskAdvanceSmart: include cleanup
release v6.5.3
RTTaskFactory: allow up to 30 turn points