Adding ign_gazebo_dev package

[harshmahesheka]

🎉 New feature

Closes #186

Summary

First,package.xml has <depend condition> which will make the package depend on the required ign-gazebo version based on Ros distribution and other packages can depend on it.Secondly, ignition_gazebo_dev-extras.cmake under cmake find and set required ign gazebo package so, other packages can simply go find_package(ign_gazebo_dev REQUIRED) instead of finding ign-gazebo which will make their packages furthermore compatible with different ROS distros. Currently, I am creating a draft pr for reviews from the community, after that, we can add similar packages for all other ignition libraries.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

Test it

1. I have created a test_package, you can clone it or replace find_package and dependencies in any of your own packages.
2. Clone this repository in your workspace and do rosdep check to see dependencies change based on your ros distro.
3. Build and source this repository and then build your test package. You can see it and find different gazebo versions based on your ros distro.

[nuclearsandwich]

I left some initial feedback and suggestions. I think this is in good shape!

[nuclearsandwich]

It is probably worth allowing an override / fallback for unofficial ROS distributions.

Using a CMake variable like OVERRIDE_ROS_GZ_VERSION or similar for override or checking ROS_GZ_VERSION environment variable to fall back to if no known ROS_DISTRO is found.

[harshmahesheka]

I have added ign fortress as an override version in ignition_gazebo_dev-extras.cmake and package.xml.

[methylDragon]

Heya @harshmahesheka I noticed this was still in draft mode :o, do we want to move forward with this?

[harshmahesheka]

Heya @harshmahesheka I noticed this was still in draft mode :o, do we want to move forward with this?

Definitely. I was waiting for approval on whether the current iteration is correct. Also, this one is just for ign-gazebo( gz-sim now), so should we create a similar folder for all other libraries in gazebo?