- methods formerly taking a const reference to Problem as input now take
    a shared pointer to const Problem.

  - add assert to check that tests are always false.

  - Specify comparison types in implicit constraint constructors.

  constraints::implicit::RelativePose has been removed.

  - replace call to deprecated method,
  - include amsmath package to generate documentation,
  - fix unit test.

  - Refactoring of ConvexShapeContact.

  Set error threshold for each internal edge to the value of the edge divided
  by the number of internal edges.

  in throwIfNotInitialized.
  This modification allows users to access constraints of some edges during
  graph initialization, as soon as those edges are initialized.

  -> generateTargetConfigOnLeaf.

  - reference ICRA 2017 paper.

  Make previous methods deprecated
  Rename Graph::configConstraint(EdgePtr_t) into targetConstraint.

  make old methods deprecated.
  This will homogeneize with hpp-manipulation-corba naming.

  - Implement method GraphPathValidation::setSecurityMargins.
  - Add method Edge::securityMarginForPair to set a security margin for
    a pair of joints along an edge.

  from is a python keyword. This is an issue when using python bindings.