Xavier launch files

[nickswalker]

Now that networking is handled, we can make the Xavier come alive on boot just like the Fetch main computer.

• Make a new Xavier launch file; it should at least run the realsense driver. Eventually, it should pop up a full screen chromium browser pointed at a particular URL so we can throw up visualizations or other UI. It can live in uw_fetch_bringup
• Write a service file for Xavier that mirrors Fetch's robot service to launch on boot. No roscore; point at the robot's master using ROS_MASTER_URI.

[nickswalker]

Note: need to include some Gnome configs as well to disable software update popups, auto lock, etc. Reference the TMC package

[nickswalker]

I'm waiting on installing ROS and dependencies until we get an initial storage expansion set up.

[nickswalker]

Add a 128GB micro sd card and partitioned it in half. When we get squeezed for space, we can consider moving /home and some other path onto those partitions.

ROS is installed, so we're good to start writing nodes to publish detection results