Update README
Update README

Add info about number of retries the GoRouter attempts before returning an error.
ryan-talley/cf-bigip-ctlr,dramich/cf-bigip-ctlr,ryan-talley/cf-bigip-ctlr,dramich/cf-bigip-ctlr,dramich/cf-bigip-ctlr,ryan-talley/cf-bigip-ctlr,dramich/cf-bigip-ctlr,ryan-talley/cf-bigip-ctlr