PageSettings: add method IsDefined()
PageSettings: use std::array

Gives us iterators and comes without overhead.
Form/ButtonPanel: add method AddSymbol()
PagesConfigPanel: use ListWidget, and an editor widget

Prepare for adding new controls to the page layout editor.  With the
old PagesConfigPanel code, this was not possible, because we're
running out of screen space.
PagesConfigPanel: show only pages that exist, add buttons

The user now deals with pages that really exist, he will not see
unused slots.  We can now remove the "---" enum choice.
PageSettings: add static methods Undefined() and Default()
Pages: add option to show cross section below map
dlgConfiguration: rename "InfoBox pages" to "Pages"

This is not just about InfoBoxes anymore.
CrossSectionWidget: enforce a range

The vector can get invalidated, but the range was never again set to a
positive value.
vlapi: SendCommandReadBulk() shift baudrate parameter

Shift baudrate parameter next to Port parameter, because
the two belong together and resolve an ambiguity problem
in the next patch
vlapi: add documentation to ReadBulk functions

Add some api documentation
vlapi: SendCommandReadBulk() implement optional longer timeout for first char

When downloading the binary log from the logger it is necessary to
wait a longer period after the first ACK is sent to the logger until
the first char is received.
This is because the logger starts calculating file security before the
first byte is sent. This may take several minutes.
The additional parameter needs to be implemented in ReadBulk() and
subsequently also in SendCommandReadBulk()
vlapi: download signature with standard IO rate

Testing has shown, that a download with bulkrate is not possible for
downloading the file signature.
Standard rate of 9600 baud has to be used at all times.
The download of the main log data however supports bulk rate.
Volkslogger igc download: create Logger.cpp

Create Logger.cpp which holds the main functions to
make Volkslogger igc file download possible from
xcsoar.
The feature is not yet activated. See separate patch
which changes the DeviceRegister (Register.cpp)
vlapi: Implement Bulkrate

Make Bulkrate configurable from UI.
This Bulkrate applies only to the download of
the actual flight log.
The download of the flight list (called DIRECTORY)
and the signature have to be carried out with
standard IO Rate 9600 baud.
9600 baud is also the minimum bulkrate supported.
DeviceEditWidget: fixed compiler warning break.
po: update Dutch translation
po: update Japanese translation
po: update German translation
po: update French translation