These times scales may be used in SP3-c files.

This detector supersedes both CircularFieldOfViewDetector and
DihedralFieldOfViewDetector, as it can handle any Field Of View shape.

This is work in progress! The detector is not tested at all.

This is related to issue #216.

Fixes issue #227

Thanks to Michael Turner for the initial patch.

Github: closes #7

Filtering is based on an user-provided enabling predicate function. This
allow for example to dynamically turn some events on and off during
propagation or to set up some elaborate logic like triggering on
elevation first time derivative (i.e. one elevation maximum) but only
when elevation itself is above some threshold.

Works for anomaly, latitude argument, or longitude argument, either
true, mean or eccentric.

Fixes issue #213.

Derivatives continuity at both endpoints of the transition can be forced
to match rotation, rotation rate and rotation acceleration.

Fixes issue #6.

Fixes issue #206.

    
Fixes issue #115.

This support is in addition to the legacy support for IERS
UTC-TAI.history file which is still supported and also enabled by
default.

Thanks to Lucian Barbulescu for providing the translation.

The Eckstein-Hechler propagator now generated Cartesian orbits, with
velocity computed to be fully consistent with model evolution. A side
effect is that if users rebuild circular parameters from the generated
orbits, they will generally not math exactly the input circular
parameters (but position will match exactly).

Fixes issue #180.