TaskManagerDialogUs.cpp: fix so not declare when "Back" button clicked
Nook.cpp: fix battery controller bug.
dlgQNH: refactor:  put class definition in separate .hpp file
InfoBoxes/Panel/BarometricPressure.cpp: new panel

Allows setting QNH
InfoBoxes/Factory.cpp: rename "Altitude barometric"

was called "Barometric Altitude"
BigTrafficWidget.cpp: make zoom ranges friendly for miles
Contest/Settings: new option to disable OLC optimisation

This a patch allows the user to disable OLC optimisation if they don't
require it.

While I was doing performance testing on the KOBO I discovered that
90% of the CPU time was spent running OLC calculations resulting in
ever other frame being greatly delayed on the draw.

For longer flights it could take several seconds to refresh the
screen, meaning that most of the info boxes were showing very delayed
information and the glider position was lagging.

This patch is quite simple and adds an option in the Task > Contest
Type box to allow a user to chose 'None'.  This will prevent any
calculation engine running and drops the CPU on the KOBO to less than
9% (and the CPU frequency down to minimum for most of the time) It
also ensures that the display continues to refresh nicely Patch should
apply to head.
GlueMapWindowEvents.cpp: allow initial drag panning everywhere

The initial drag panning was halting if the screen was returned to
an area close to its original origin.  Now it is smooth
GlueMapWindowEvents.cpp: leave screen in mouseup position on pan

when the drag-to-pan starts and the mouse is lifted the
first time, leave the screen panned in this position.
GlueMapWindowEvents.cpp: make pan threshold smaller on touchscreens