Fix scripts and templates within UUV Assistants

[MaxxWilson]

Reference Issues/PRs

None

What does this implement/fix?

This fixes issues and typos found when configuring a new vehicle and a new thruster manager according to the UUV Sim documentation.

Change List

• Replace "colcon_create_package" call with the proper "ros2 pkg create" in UUV Assistants scripts
• Change references from $CATKIN_PACKAGE to $COLCON_PACKAGE in robot model templates
• Fix broken parameter scoping in thruster manager config template
• Adds templates for python launch files for packages created with UUV Assistants
• Adds installation of launch and config directories into CMakeLists for packages created with UUV Assistants
• Remove unused imports for roslib and rospkg. These aren't needed and aren't installed with the listed dependencies.

Additional Comments

Passed all automated tests on my end. I also configured a new vehicle and thruster manager from scratch following along with the UUV Sim docs and it should work.