add vendor documentation to hacking.txt
add vendor documentation to hacking.txt

oneclickorgs/one-click-orgs,oneclickorgs/one-click-orgs-deployment,oneclickorgs/one-click-orgs-deployment,oneclickorgs/one-click-orgs,oneclickorgs/one-click-orgs,emmapersky/one-click-orgs,oneclickorgs/one-click-orgs-deployment,oneclickorgs/one-click-orgs,emmapersky/one-click-orgs