Rename to game_controller_spl

[Flova]

This PR renames everything to game_controller_spl. We would still need to rename the repo (I don't have the permission).

This makes it consistent with https://github.com/ros-sports/game_controller_hl

Closes #77

[ijnek]

Thanks for starting this change @Flova, while the changes look good, these packages are already released and a tik-tok deprecation strategy is necessary to ensure teams that rely on this (there are a few), don't suddenly have code that doesn't work.

Would you be able to add the new packages, but leave the old packages there, and add a deprecation tag in in package.xml, as following?

  <export>
    <build_type>ament_python</build_type>
    <deprecated>
      Please use game_controler_spl. gc_spl will be removed in K-turtle.
    </deprecated>
  </export>

[ijnek]

Due to some complications elsewhere with deprecation of packages, i've gone ahead and rebased and made the changes. Once CI passes, this will be merged.

[ijnek]

Thanks for this improvement @Flova !