Add icmp type/code to dynamic egress docs
Add icmp type/code to dynamic egress docs

- also clean up trailing spaces and spaces vs tabs

[#161161673]

Signed-off-by: Tyler Schultz <6b7a73f4f7cffc2a148becd12890940350ddfa95@pivotal.io>

cloudfoundry-incubator/cf-networking-release,cloudfoundry-incubator/cf-networking-release,cloudfoundry-incubator/cf-networking-release,cloudfoundry-incubator/cf-networking-release