Use Boost_LIBRARY_DIRS as well as Boost_LIBRARY_DIR
Use Boost_LIBRARY_DIRS as well as Boost_LIBRARY_DIR

The later is used by CMake < 3.0 while the first is used for CMake >=
3.0

gergondet/RBDyn,gergondet/RBDyn,jrl-umi3218/RBDyn,gergondet/RBDyn,jrl-umi3218/RBDyn,gergondet/RBDyn,jrl-umi3218/RBDyn,jrl-umi3218/RBDyn,gergondet/RBDyn