Remove the dynacom and the deprecated functions to compute dynamics in bipedIG

[NahuelVilla]

We are releasing a new package containing the class dynacom and the contacts.

Such classes should be removed from this repository. Do we shoot a warning on it, or we just remove that code?

[NahuelVilla]

The dynacom repo can be found here:

https://github.com/Gepetto/dynacom