Now that TLEPropagator really implements the Propagator interface (by
extending AbstractPropagator), it really makes sense to have this
package
here.

This change will allow using this class for other kind of propagators.

FastMath.atan2 *is* well defined when both x and y are 0 (just as
Math.atan2 or any IEEE754-compliant implementation), there is no need
to perform an additional check against 0 before calling this method.

The geometry packages have been renamed (again) from oneD, twoD,
threeD to oned, twod, threed. Hopefully, this should be the last name
change.

The classes that were formerly in org.apache.commons.math.geometry are
now in org.apache.commons.math.geometry.euclidean.threeD. This change
is a side effect of the inclusion of a complete BSP trees
implementation in Apache Commons Math.

Previously, they arbitrarily used on hundredth of the Keplerian
period as the step size, hence performing many steps even if not
strictly required. Now the step size is equal to the duration of the
propagation in all cases except when a fixed step is requested in
master mode. 

This change will allow using the new public APIs concerning root
solvers, optimizers, ODE integrators, linear algebra, geometry,
statistics and error handling. It also solve numerous bugs, some of
them affecting Orekit. Vesion 2.2 is considered obsolete now.

Synchronizing major releases for both Apache Commons Math and Orekit
is also much simpler for users, who will not feel the pain of two
successive changes.

Conflicts:
	src/main/java/org/orekit/propagation/AnalyticalPropagator.java
	src/main/java/org/orekit/propagation/events/AdaptedEventDetector.java
	src/main/java/org/orekit/propagation/numerical/NumericalPropagator.java
	src/site/xdoc/changes.xml

Mapping between orbits and state vector is now done in a more general
way and ensures consistency between orbit type and mapping.

The previous implementation:
 1) was much more complex,
 2) required support from the propagators themselves,
 3) did not allow logging only a subset of the events,
 4) included internal events like the ones used by some force models

Some data may be negative, the minus sign was missing in the regular
expression pattern, preventing file loading with a line nor recognized
error.

Now Jacobians numerical propagation is supported in Cartesian,
circular, Keplerian and equinoctial elements, and for the last three
orbit types the position angles can be either true, eccentric or mean
angle.

Also allowed numerical propagation in circular parameters.

This changes greatly simplifies the numerical propagation handling and
allows easier extensions (any new Orbit implementation will
automatically be supported out of the box by the numerical propagator.

Relying directly on orbit Jacobians allow to support numerical
propagation for hyperbolic orbits in addition to elliptical orbits.

the packaging has been updated for compliance with deployment to
maven central (fixes bug #17).