All resource files should have matching line numbers, it helps managing
messages properly.

The attempt failed, but needs more investigation, so we keep it.

Conflicts:
	src/changes/changes.xml

Fixes #872

Added atmospheric drag effect for Brouwer-Lyddane model.

Closes #871

See merge request orekit/orekit!224

Fixes #871

This is a partial implementation for issue #855.

The names should *not* be extracted too early, at least the force models
must be completed before they can be retrived reliably. However, once
they are set up we can ask the MatricesHarvester to give the columns
names, even if propagation has not started yet.