[orocos-kdl-python] install PyKDL to site-packages instead of dist-packages

[acxz]

From @daizhirui in #265

PyKDL is used by tf2-sensor-msgs. dist-packages is not included in the sys.path by default. It is recommended to use site-packages instead. site-packages is used when building this package with ROS activated.

[acxz]

patched with fadda6f

[acxz]

@daizhirui when you get the chance you link an upstream issue regarding the patch you created? Thanks!

[daizhirui]

@acxz I create a pull request at the upstream: orocos/orocos_kinematics_dynamics#471