po: update Lithuanian translation
Driver/LX: auto-retry after errors during IGC download
Event/Linux/Input: don't use "pressed"/"released" with old position

Commit 9d028db6 implemented EV_SYN/SYN_REPORT, which means finger
movement was not committed by Generate() until this event was
received.  However BTN_TOUCH did not follow this rule, and thus the
finger position reported by these was the last known finger position,
not the new finger position (TRAC #3195, #3211).

This commit fixes the regression by splitting "pressed"/"released" to
two new attributes: "pressing"/"releasing" specifies uncommitted
changes, to be committed by EV_SYN/SYN_REPORT.
Screen/Util: fix signed/unsigned mixup in IsCircleVisible()

Fixes disappearing observation zones at left/top screen border
(#3212).  Problem was an integer underflow due to casting a negative
number to unsigned.
Driver/LX: full flush after binary handshake

According to the logs submitted at TRAC #3199, the handshake often
fails because there are pending ACKs.  This commit tries harder to
flush the port before sending the first real command to the device.
MapWindow: fix inverted BrokenDateTime::IsPlausible() check

Fixes RASP display (regression by commit a539688f).
LocalPath: fix typo in code comment
LocalPath/Android: load XCSoarData from external SD card if available

If XCSoarData exists on a writable exists SD card, choose that path as
the primary data path (implements TRAC #3198).
OS/{File,Socket}Descriptor: make the "int" constructor explicit

Avoid accidental implicit cast.
OS/SocketDescriptor: explicitly instantiate move ctor+operator

On WIN32, the compiler is unable to generate them automatically,
because there is a destructor  (TRAC #3214).
Gauge/FlarmTrafficWindow: move code to FlarmColorPen()

Easier to read and works around a clang analyzer warning by declaring
FlarmColor::COUNT "unreachable".
XML/Parser: eliminate useless GetNextChar() call
TaskFileSeeYou: move code to CalcIntermediateAngle()

Adds a fallback for unknown/invalid style.  Previously, XCSoar could
use an uninitialized variable which could do funny things.  gcc had
been warning about this problem for years, but we never cared enough
for it (TRAC #3213).
Logger/MD5: work around strict-aliasing warning
NEWS.txt: add TRAC #3204
Event/TTYKeyboard: add missing Compiler.h include

Required for "final" on old compilers.
release v6.7.3
Manual en xc_tasks: Updated, auto waypoint "takeoff" included.
Manual en: Tiny typos and formulation.
Manual figuers: Reminder icon with a slicker round dot.