update to cope with disparition of has_parent
remove algorithms from the generated files
remove jacobian from the generated file

this jacobian is not used in the upstream metapod
add a simple_arm example urdf
add a libname option
fix order of namespace closing comments
update todo list
catch program_option exceptions
use the metapod_robotbuilder library

the metapodfromurdf library has ben removed. The metapod_robotbuilder
library is used instead.

The metapodfromurdf-bin binary has been renamed metapodfromurdf and
improved.

The simple-arm version generated from urdf can now replace the original
one from metapod. Metapod tests pass with it.
add simple_humanoid example

Copied and adapted from https://github.com/laas/simple_humanoid

The model generated from this data builds, is not totally identical to the
example from metapod:

 * the one from metapod has all its axes oriented along the X-axis
   this one has the oriented along X, Y or Z. As a consequence, the
   generated model uses a combination of REVOLUTE_AXIS_X and
   REVOLUTE_AXIS_ANY.

 * the joint::positionInConf from the metapod model does not follow
   the ordering of the joint. As a consequence, the two models do
   not load the configuration vector the way.

Because of the second problem, the tests do not pass.

Maybe it could work in the zero configuration.

A solution would be to let the user customize each joint positionInConf.
provide dof index

and use it to generate simple_humanoid
update simple_humanoid.urdf

with this fix, all the simple_humanoid tests pass with the only exception
of bcalc: each frame position is good, but the orientation is not, some
axis are permuted.

This is expected since the frame definitions are not identical.

The rnea and crba tests work as expected since they operate in configuration
space work.

The various jacobian tests also work because the compute the world
velocites of the links, not the body velocity.
update to follow robotbuilder API changes