This directory contains vendored repositories.
Use vendor.sh to manage vendored repositories:
Usage:
vendor.sh add <repo-url> <ref> [name]
vendor.sh list
vendor.sh update <name> <ref>
<ref> specifies which branch/tag/commit to check out in the vendored
repository.
<name> is the name of the subdirectory in 'vendor/'. By default, it is
inferred from the repository URL.