remove the dependency to xunit-performance
remove the dependency to xunit-performance

ViktorHofer/corefx,shimingsg/corefx,ericstj/corefx,ericstj/corefx,ViktorHofer/corefx,wtgodbe/corefx,wtgodbe/corefx,shimingsg/corefx,wtgodbe/corefx,ericstj/corefx,ericstj/corefx,ViktorHofer/corefx,ericstj/corefx,shimingsg/corefx,BrennanConroy/corefx,shimingsg/corefx,shimingsg/corefx,ViktorHofer/corefx,ViktorHofer/corefx,BrennanConroy/corefx,shimingsg/corefx,shimingsg/corefx,ViktorHofer/corefx,ericstj/corefx,wtgodbe/corefx,ericstj/corefx,ViktorHofer/corefx,BrennanConroy/corefx,wtgodbe/corefx,wtgodbe/corefx,wtgodbe/corefx