The timer was only started in _logData(), which was called after receiving
the first chunk of data (and only if that was successful), which means
if the first request failed or timed out, the UI would never switch to
a timed out state.

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Still does not support multi-vehicle

On large/high DPI screens, the whole UI scales nicely when increasing the
font size, except for the attitude widget, that was limited to 200 pixels.

save to kml use double number with 10 valid digits。

On PX4, under certain circumstances and in rare cases, there can be log
files with 0 size. In that case QGC ignored the entry and tried to
re-request the entry indefinitely.

mobile needs more testing before we can enable this.
A test on an android phone was successful however.

helpful for example when editing parameters

If there are dropped packets during a burst download, the offsets and sizes
of the missing chunks are stored in a queue, and after the burst is
completed, they're requested individually.

This stores the last request and resends it after a timeout, with a max
of 6 retries.
It also checks for old incoming packets and drops them.