More specifically take into account the new headers of
abstract-robot-dynamics.

This commit allows to change on-line the constraints applied on the
feet. On-line modification such as in Dimitar2007, allows to script
the constraints modification. This calls for a proper synchronization
of information better handled in a separate class FootHalfSize.

Those values work for HRP-2, but prevented regression tests
with sample-humanoid-robot.

Reinforce policy to not externalize internal types.
This will help contributors by allowing internal
changes without impacting users.

Wrong return value on EndPhase of the walking.
This commit compiles.

The variable name was using capitals letter for
differenciation. Added FOR_VEL_REF.

Please DO NOT put types in the API which are not necessary
to interact with the user. This should stay in the private
area.

Conflicts:
	src/ZMPRefTrajectoryGeneration/ZMPVelocityReferencedQP.cpp
	src/ZMPRefTrajectoryGeneration/ZMPVelocityReferencedQP.h

Trailing spaces should be removed to ease code comparison.

This reverts commit c8afc3f3.

This reverts commit 7c4555db.