Update README for enabling routing api on bosh-lite
Update README for enabling routing api on bosh-lite

[#115654277]

Signed-off-by: Iryna Shustava <2d2404266b0a0832518fb8eeb9ad53e987c2cdbe@pivotal.io>

cloudfoundry-incubator/cf-routing-release,cloudfoundry-incubator/cf-routing-release,cloudfoundry-incubator/cf-routing-release