* Extending `rewritten_yaml` to also replace keys.

* Adding a node launcher that puts a condition to
applying the remappings.

* Add namespacing of launch files.

* Update namespace of costmap and passing of correct
namespace by planner & controller.

* Add back parameter to configure DWA rate

* Report out if we missed our control loop time.

serverIsActive to is_server_active

deleting robot package

Extended the SimpleActionServer interface and improved a few other things:
* Added additional checks to make sure we only keep the latest preempt request in the queue.
* Action server users no longer interact directly with the goal handles. 
* Provided additional functions for aborting, canceling, etc.
* Updated bt_navigator, motion_primitives, dwb_controller, navfn_planner to use the new interface.

Refactored the DWB controller main loop.
* Added checks for handling pending preemptions after the controller has succeeded or failed.

* Precise control of the contained node to improve shutdown reliability

* Add a couple TODO comments about further reducing code, eliminating duplication

* removing recovery test tree

* changed amcl to publish pose only when initial pose is known

* update transform only when initial pose is known

* fixed linter issues

* print when amcl does not publishes a pose

* changed publishing velocity msg from rclcpp_info to rclcpp_debug

* fixed uncrustify

* removed unused variable

* deleted unused code

* disabled localization test

* Move the temporary lifecycle headers to nav2_util

* Also update the package.xml and CMakeList.txt files

* Minor patch-up after rebasing and testing

In the future, there can be some error recovery here.

* Port DWB to ROS2 actions and update for ROS2 parameter changes

* Remove the rate monitor-related code (not ready for check-in yet)

* Remove a callback related to rate monitoring

* Address some review feedback

* More review feedback

* Port the dwb code to lifecycle nodes

* Add a few missing dependencies & some misc. fix-ups

* Address some review feedback

fix extra line space

* Add progress checker

* Fixing linter errors.

* Making method naming convention consistent.

* Fixing loop rate.

* Display actual controller loop rate info.

* Integrate example code into the DWB controller main loop
* Changes to get current robot pose from global planner, required for dynamic replanning
* Address review feedback
* Fix cpplint problem

* Initial work on running planning and control in parallel
* Checkpoint a working version with lots of debugging traces
* Remove debugging traces
* Remove the temporary hooks
* Address lint issues
* Remove some debug output
* Fix a compile problem after taking out some debug code
* Read the BT XML from an external file
* Re-enable DWB code
* Address reviewer feedback

* Getting started; not working yet
* Update the unit test
* Fix issue #44 to modify TaskServer to accept a ROS node rather than be a ROS node

Updated the TaskClient and TaskServer templates to accept a rclcpp::Node::SharedPtr
reference. Also updated the Robot class to do the same. Also had to then change
the execute method to be set on the TaskServer rather than have derived classes
override the method. Now, it is more like the SimpleActionServer from ROS1,
which sets us up a bit better for the port to Actions when ready on ROS2.

* Rename various execute methods to be specific now that they are not overrides of a base class virtual method
* Costmap service name should just be GetCostmap