Sramp 511

https://issues.jboss.org/browse/SRAMP-511
Yes the installer should create it.  But I can imagine a future where we're mostly using default properties and the installer doesn't create that file.  Also it seems like if the file is not there, then the command has enough information to create it.  The following properties (I would think) should get created:

overlord.auth.saml-keystore=${sys:karaf.home}/etc/overlord-saml.keystore
overlord.auth.saml-keystore-password=123admin!
overlord.auth.saml-key-alias=overlord
overlord.auth.saml-key-alias-password=123admin!