Bugfix in the example and added attitude correction (roll and pitch for now).

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Updated doc and copyright
Fix attitude
Try fixing nadir.
Computations for true nadir.
Cosmetics.
Merge branch 'pre-master' into geoloc
Add sun_earth_distance_correction function.
Merge branch 'master' into geoloc
vectorize the days function.
Merge branch 'feature-vectorize' into geoloc
get_zenith_overpass replaced by Martin's get_next_passes
Add geoloc example.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Merge branch 'geoloc' of github.com:mraspaud/pyorbital into geoloc
Cosmetic, be consistent in name og time argument as 'utc_time'
Add instrument examples for geoloc.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Add Mikhail's definition of AMSU-A
Factorize avhrr code (geoloc definition)

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Make the scan angle of avhrr an argument.
Fix syntax error in doc/conf.py