Clear Costmap during Runtime

[erickmu1]

Description:

• When testing Caffeine, anything identified on the costmap as obstacle remains there as one
• To avoid having to restart Caffeine every time an undesired obstacle is recorded or the costmap becomes messed up, we need a way to reset the costmap without restarting all of Caffeine
• Essentially, this will decrease the time required between test cycles

Goals:

• Clear costmap without having to restart caffeine_gazebo.launch or caffeine_setup.launch

Acceptance Criteria:

• Costmap is cleared and robot can resume navigation just as if it had just been turned on

Notes:

• Stopping Gmapping and restarting is a valid option, but the general issue is that it won't work if the robot is not at its spawn pose