Setup: Add ACS setup instructions
Setup: ACS and certificates
 * Add instructions to PrivateConfigSetupGuide for setting up ACS
 * Rewrite MakeCerts.cmd for generating self-signed test certificates
 * Add wfetch-ps.cmd (stand-in for wget that uses PowerShell)
 * Add X509FromFederationMetadata.cmd to extract ACS X509 from downloaded WS-Federation Metadata (using regex utility)

TODO: Add certificate generation instructions to guide + script to install certificates on dev machines