update depricated api's

[dwijaybane]

catkin_make fails with following error msg:

/notebooks/catkin_ws_kinetic/src/pgm_map_creator/src/collision_map_creator.cc: In m
ember function ‘virtual void gazebo::CollisionMapCreator::Load(gazebo::physics::Wor
ldPtr, sdf::ElementPtr)’:
/notebooks/catkin_ws_kinetic/src/pgm_map_creator/src/collision_map_creator.cc:35:23
: error: ‘class gazebo::physics::World’ has no member named ‘GetName’
     node->Init(world->GetName());
                       ^
/notebooks/catkin_ws_kinetic/src/pgm_map_creator/src/collision_map_creator.cc: In m
ember function ‘void gazebo::CollisionMapCreator::create(gazebo::CollisionMapReques
tPtr&)’:
/notebooks/catkin_ws_kinetic/src/pgm_map_creator/src/collision_map_creator.cc:91:55
: error: ‘class gazebo::physics::World’ has no member named ‘GetPhysicsEngine’
     gazebo::physics::PhysicsEnginePtr engine = world->GetPhysicsEngine();

Two Changes:

• Instead of physics::PhysicsEnginePtr engine = world->GetPhysicsEngine();
  use physics::PhysicsEnginePtr engine = world->Physics();
  ref forum

• Instead of node->Init(_parent->GetName());
  use node->Init(_parent->Name());
  ref forum

[lalten]

I'm using this in a container based off osrf/ros:kinetic (because Udacity's RoboND stuff is so old that it really doesn't work on anything newer than kinetic 🤦). Anyways, with this merged, I'm running into:

Scanning dependencies of target collision_map_creator
[ 62%] Building CXX object pgm_map_creator/CMakeFiles/collision_map_creator.dir/src/collision_map_creator.cc.o
/catkin_ws/src/pgm_map_creator/src/collision_map_creator.cc: In member function ‘virtual void gazebo::CollisionMapCreator::Load(gazebo::physics::WorldPtr, sdf::ElementPtr)’:
/catkin_ws/src/pgm_map_creator/src/collision_map_creator.cc:35:23: error: ‘class gazebo::physics::World’ has no member named ‘Name’
     node->Init(world->Name());
                       ^
/catkin_ws/src/pgm_map_creator/src/collision_map_creator.cc: In member function ‘void gazebo::CollisionMapCreator::create(gazebo::CollisionMapRequestPtr&)’:
/catkin_ws/src/pgm_map_creator/src/collision_map_creator.cc:91:55: error: ‘class gazebo::physics::World’ has no member named ‘Physics’
     gazebo::physics::PhysicsEnginePtr engine = world->Physics();
                                                       ^
pgm_map_creator/CMakeFiles/collision_map_creator.dir/build.make:62: recipe for target 'pgm_map_creator/CMakeFiles/collision_map_creator.dir/src/collision_map_creator.cc.o' failed
make[2]: *** [pgm_map_creator/CMakeFiles/collision_map_creator.dir/src/collision_map_creator.cc.o] Error 1
CMakeFiles/Makefile2:1145: recipe for target 'pgm_map_creator/CMakeFiles/collision_map_creator.dir/all' failed
make[1]: *** [pgm_map_creator/CMakeFiles/collision_map_creator.dir/all] Error 2
Makefile:138: recipe for target 'all' failed
make: *** [all] Error 2
Invoking "make -j4 -l4" failed

For now, I can just git checkout 71671246557319de3abd4628b879efe8defacdf8 and the build succeeds.

@abhiojha8, please test stuff before you merge it. If you don't update the rest of the course material to something non-ancient, you should probably create branches for the various Ros distros like other packages do.