FRI 2.x support

[mhubii]

In favor of #85.

Refers to #156.

• FRI message updates:
  • Cartesian pose support
  • Commanded joint position removal

Related issues

• Add support for FRI ver2.5 #85
• Server App for FRI 2.5 fri#8 (to be provided)
• Unsure how to use this package with custom FRI version? fri_vendor#2
• Check fri availability to allow offline build fri_vendor#1
• FRI 1.11 fri#19
• FRI 1.16 fri#20
• ROS development tools in readme  #145

Compilation e.g. via (vendor fetches via branch https://github.com/lbr-stack/fri_vendor/blob/b714a6e4d9e4c0ac2b0925b657f97e1d11fcd378/CMakeLists.txt#L18)

colcon build --symlink-install --cmake-args -DFRI_CLIENT_VERSION=2.5 --no-warn-unused-cli

Requires:

• Pre-processor macros in lbr_fri_ros2 package
• Position mode message definitions
• Fix of (no problem but annoying): --no-warn-unused-cli CMake unused variable warnings in ROS2 workspace colcon/colcon-ros#83

  CMake Warning:
    Manually-specified variables were not used by the project:

Alternatives:

• Standard installation (no ament_cmake stuff)
• Removal of vcs clone in favor of separate cloning step

Nice to have:

• Build and test matrix