Samuel Flis / gammalib

# Conflicts:
#	ChangeLog
#	NEWS
#	doc/source/admin/release_history/index.rst

The smoothing kernel covered before only two sectors, now all four sectors are covered. The smoothing now also works correctly in case that more than a single sky map is comprised in a GSkyMap object.

…d::save() methods to Python interface and avoid segfault in GObservations::likelihood::covariance() method for non-allocated curvature matrix

The observation identifier is now stored in the generic GObservation::id() attribute.

…TE-END, TIME-OBS and TIME-END

…ACubeExposure (#2295)