The API reference document had a typo where the "X-Forwarded-Port"
parameter for the HTTP header insertions was listed as an integer
instead of as a string. It also corrects "X-Forwarded-For" to be a
string. This patch corrects that mistake.
Change-Id: I3996d5e1950f8d979eb1c354dfac70a0ddefdca2
aab5e6645f