Removed SphericalObstacleData

It hadn't been used for quite a while and was there just for backwards
compatibility.  You should use DetectableObject moving forward.
Adding namespaces to all behaviors
LookLikeInspector is deprecated on Unity 4.3
Removing unnecessary indentation on DetectableObjectEditor
SteeringEvent was not really necessary, removed

We'll just use System.Action, and pass a radar or vehicle parameter.

New property Steering.ShouldRetryForce to indicate if the steering
should retry its force calculation. This previously used the Action on
SteeringEvent, something I was never really happy with.
BUGFIX: Should only set ReportedArrival if we didn't set a new force
REFACTOR: Repulsion's intersection find method is now static

There was no particular reason to have that be an instance method, since
we can just pass the vehicle as a parameter instead of just its position.

I'll likely move it to an independent tool class in the future, since I
may have use for it on other behaviors.
Updating changelog
BUGFIX: SteerForPursuit was drawing the debug force incorrectly
SteerForTether is now a post-processing behavior

This makes more sense, since the tether itself should be a correction
force on the vehicle's desired velocity, not a force in and of itself.
SteerForEvasion is now a post-processing behavior

This helps overlay it with other behaviors in a more natural fashion,
since we can steer the vehicle while still keeping away from a target.
SteerForPursuit now can optionally use the full approach force

Previously we were using the default value for GetSeekVector, which
subtracts the velocity from the approach vector.  The default is now to
apply the full force.
Vehicle Speed and Velocity no longer have a public setter

See accompanying changelog for rationale.
Handling possible TickedVehicle de-queueing issue
New TickedPriorityQueue, logging Vehicle tick exceptions
TickedPriorityQueue now handles dequeueing case mentioned on 73887cd
Removed leftover code, clarified velocity vector. See issue #8.

https://github.com/ricardojmendez/UnitySteer/issues/8
MAJOR CHANGE: New handling of acceleration/deceleration smoothing

- New properties to control acceleration and deceleration rates for
  autonomous vehicles.
- Speed no longer has a setter.
- Renamed UpdateOrientationVelocity to the clearer UpdateDesiredVelocity.

See http://arges-systems.com/blog/2014/01/30/unitysteer-acceleration-smoothing-changes/

Considered adding a curve for the deceleration, but haven't decided yet
what would be some easily understandable units to express it in. My
current thinking if that if someone wants that sort of fine-grained
control over acceleration/deceleration, there is always the possibility
of subclassing AutonomousVehicle or creating a post-processing behavior.
SteerForNeighbors.CalculateForce should not be overridable
New SteerForMatchingVelocity behavior

See remarks for the rationale and how it's distinct from *Alignment.