As it uses std::weak_ptr

Changes since v1.1.1:
- fixed .pc
- updated CMake

Because, with a recent CMake, if doc/header.html is provided and the
build folder is the root folder, this file gets overwritten by itself,
disappears, and therefore can't be installed.

fix configure on Arch for ignition-common1

to fix build of wip/prf-ros-controllers on 16.04 & python3

Changes since v3.4.1:
- Improve doc
- Switch to modern CMake
- Add package.xml

To fix version in package.xml, and therefore in the .pc generated by
catkin

to be able to depend on the c++ package without the python option

As they are not in robotpkg anyway.

Use:
- wip/prf-gazebo-ros-pkgs-melodic on 18.04
- wip/prf-gazebo-ros-pkgs on 16.04
- simulation/gazebo-ros-pkgs otherwise

To plan ahead for next version.

To plan ahead for next version.

To plan ahead for next version.

While here, set USE_PYTHON_ONLY

Changes since v0.3.0:
- [CMake] add INSTALL_PYTHON_INTERFACE_ONLY option
- Update README

Packaging changes:
- Split the package into c++ headers & python bindings

to add the missing dependency to pinocchio on some targets

As the other talos & tiago related packages.

Changes since v3.8.0:
- CMake: rollback to old version for eigen3 & boost

Changes since v3.7.3:
- package.xml
- Modern CMake