Create own exploration node

[bntti]

Acceptance criteria

• The robot always moves to the next unexplored area, until there are no unexplored areas left. (The implementation could use OccupancyGrid)
• The robot stops, for example, every 1 meter and then turns 360 degrees to find the QR codes
• The autonomous exploration should continue exploring even after the entire area has been explored
• The autonomous exploration node should be able to navigate to a given QR code. (Ideally the robot would position itself straight in front of the QR code)

Story tasks

• Figure out how we would implement our own exploration node #51
• Implement the autonomous exploration part of the exploration node #52
• The robot stops and spins every x meters while exploring #55
• The exploration node continues exploring even after the whole area has been explored #57
• The exploration node has support for controlling it #59
• The exploration node can navigate to a given location / QR code #62