Resource.Manifest is a PowerShell module providing commands to define resource manifests made of resource groups —i.e. resources grouped by kind. Resource manifests are declarative Microsoft BizTalk Server® deployment recipes that can be entrusted to the BizTalk.Deployment PowerShell module, which will determine how a manifest's resources have to be deployed and in what order.
In order to be able to install the PowerShell module, you might have to trust the be.stateless's certificate public key beforehand; see these instructions for details on how to proceed.