This also fixes scrolling

* Add support for another board

* Added a 2nd custom board

Update Windows and OSX to specify 1.5.2 usage, plus links.

Seems to work differently on appveyor build

Also report the current transfer rate in the currently downloading status to help expose regressions in performance.

Also updated some docs

first iteration of mission stats calculation (dist and maxTelem)

add survey item distance to mission distance

remove unused calculations from _calcHomeDist

added correct calculation of missionMaxTelemetry when there is a complex item

use speed to compute mission time according to vehicle type

started implementation of hover and cruise distance

corrected typos

added logic

prevent survey from crasing

added checks for vtol

rearrange logic

added primitive check for landing

rearranged checks

new arrangement

added logic for transition

fix for small bugs

add check for mission speed larger than 0

remove already existinh check

reduce code a bit

clean up