Adding support for nav2D flat nav. Adding some existing ROS params to…

[mjstn]

• Adding launch files for new 'flat' navigation or nav2D mode.
• Additions to move_basic.launch for better visibility from launch file.
  Am trying to set the current software defaults in cpp files OR use what was in prior launch

The required 'flat' nav launches include these:
High Level Read Only mode: simple_navigation_flat.launch
aruco: aruco_navigation_flat.launch

[davecrawley]

Do a comparative test of flat nav vs. 3-D nav.

[mjstn]

First I suggest getting our existing nav to work so use this page:
https://github.com/UbiquityRobotics/learn/blob/master/doing_more/fiducials.md

For now do NOT run the simple_navigation_flat.launch because to do that requires some special configuration.

Get the existing mode to work will get you a LONG ways in that you can evaluate existing mode which is 1/2 of this issue.

YOU MUST TAKE SPECIAL CARE TO SETUP YOUR UPWARD CAMERA WITH GREAT CARE. Get it as close as you can and then just remember that the robot may be off by as much as 10cm depending on what direction it approaches the fiducials.

Also play with and become familiar with the move_patterns.py script which is linked to at the end of above learn page. I include link here as well:
https://github.com/UbiquityRobotics/move_basic/blob/kinetic-devel/scripts/move_patterns.py

After this is all running THEN we will test flat navigation.