added api for rospack to determine package type
added api for rospack to determine package type

wkentaro/rosdep,allenh1/rosdep,wkentaro/rosdep,ros-infrastructure/rosdep,aymanim/rosdep,alessandro-aglietti/rosdep,spaghetti-/rosdep,georgepar/rosdep,georgepar/rosdep,ros-infrastructure/rosdep,alessandro-aglietti/rosdep,allenh1/rosdep,sorki/rosdep,aymanim/rosdep,spaghetti-/rosdep,sorki/rosdep