add missing expose to code example
add missing expose to code example

ryanpetrello/pecan,jimrollenhagen/pecan,StackStorm/pecan,citrix-openstack-build/pecan,StackStorm/pecan,jdandrea/pecan,jimrollenhagen/pecan,pecan/pecan,pecan/pecan,ryanpetrello/pecan,jdandrea/pecan,citrix-openstack-build/pecan