Add script to parse a gazebodistro file and create all vendor packages

[azeey]

This is a convenient tool for creating/updating vendor packages based on the branch names in a gazebodistro file

[scpeters]

Thanks, this is a great script! I added an --output_dir argument in c15ceb0 that will write each vendor package as a subfolder of that directory like:

<output_dir>/gz_cmake_vendor
<output_dir>/gz_utils_vendor

and then I ran the following command to update the gz-cmake, gz-tools, gz-utils, gz-math, and sdformat vendor package pull request branches that were already open as part of gazebosim/gz-jetty#38

# assuming that ~/ws/jetty/src/collection-jetty.yaml exists with the right content
python3 create_gz_vendor_pkg/gz_vendor_all_libs.py \
  jetty \
  --suffix_from_cmake \
  --overwrite_cmake_configs \
  --output_dir=$HOME/ws/gz_vendor_sdformat/src/gz_libs

since I already had the vendor packages cloned at ~/ws/gz_vendor_sdformat/src/gz_libs/. I then committed the additonal changes to these branches

• Jetty support: bump to 5.0.0, fix package names gazebo-release/gz_cmake_vendor#16

• Jetty support: minor updates gazebo-release/gz_tools_vendor#9

• Jetty support: bump to 4.0.0, fix package names gazebo-release/gz_utils_vendor#11

• Jetty support: bump to 9.0.0, fix package names gazebo-release/gz_math_vendor#12

• Jetty support: bump to 16.0.0, fix package names gazebo-release/sdformat_vendor#16

[scpeters]

the script works; we should document how to use it in the README

[scpeters]

nit: this path is a bit hard-coded

[azeey]

This was a workaround for getting rate limited. Normally, the get_collection function should be used to download the collection from Github. I've left this for now and made a change at the callsite to use get_collection.