Add hearbeat functionnality.
Finalize heartbeating.
bugfix
Now reads satellite id from hrpt frame instead.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Don't use the filename to know the year of the hrpt data.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Do the satellite check after the hrpt_sync check for sanity.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>