Modify netci.groovy to support selfhosted outerloop
Modify netci.groovy to support selfhosted outerloop

PR #1083 adds support for testing outerloops against SelfHostedWcfService, so we
need a similar mechanism to do so in CI as well

iamjasonp/wcf,ericstj/wcf,imcarolwang/wcf,shmao/wcf,dotnet/wcf,hongdai/wcf,zhenlan/wcf,hongdai/wcf,ElJerry/wcf,ericstj/wcf,dotnet/wcf,KKhurin/wcf,StephenBonikowsky/wcf,MattGal/wcf,dotnet/wcf,MattGal/wcf,mconnew/wcf,imcarolwang/wcf,mconnew/wcf,KKhurin/wcf,iamjasonp/wcf,shmao/wcf,mconnew/wcf,StephenBonikowsky/wcf,imcarolwang/wcf,zhenlan/wcf,ElJerry/wcf