Restructured directories

[ahcorde]

Signed-off-by: ahcorde ahcorde@gmail.com

🦟 Bug fix

Summary

I can't release the packages with the current directory structure, because the old ones were already released with this directory structure.

This PR should fix the issue with the bloom process.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[methylDragon]

Do the version numbers for the shim packages need to be bumped?

[methylDragon]

It might be good to leave a note in the README also.

Note: The `ros_ign` prefixed packages are shim packages that redirect to their `ros_gz` counterpart.
Under most circumstances you want to be using the `ros_gz` counterpart.