Add defaults and env control of the fin timeouts in the router

Set defaults for the fin timeouts and expose them as environment
variable controls to the user.

The new environment variables are:
 - ROUTER_CLIENT_FIN_TIMEOUT: Controls the fin timeout to the client of
     haproxy (default 1s)
 - ROUTER_DEFAULT_SERVER_FIN_TIMEOUT: Controls the fin timeout to the
     server haproxy contacts, i.e. in the cluster (default 1s)

images/router/haproxy/conf/haproxy-config.template

@@ -64,11 +64,21 @@ defaults
 {{- else }}
   timeout client 30s
 {{- end }}
+{{- if (matchPattern "[1-9][0-9]*(us|ms|s|m|h|d)?" (env "ROUTER_CLIENT_FIN_TIMEOUT" "")) }}
+  timeout client-fin {{env "ROUTER_CLIENT_FIN_TIMEOUT" "1s"}}
+{{- else }}
+  timeout client-fin 1s
+{{- end }}
 {{- if (matchPattern "[1-9][0-9]*(us|ms|s|m|h|d)?" (env "ROUTER_DEFAULT_SERVER_TIMEOUT" "")) }}
   timeout server {{env "ROUTER_DEFAULT_SERVER_TIMEOUT" "30s"}}
 {{- else }}
   timeout server 30s
 {{- end }}
+{{- if (matchPattern "[1-9][0-9]*(us|ms|s|m|h|d)?" (env "ROUTER_DEFAULT_SERVER_FIN_TIMEOUT" "")) }}
+  timeout server-fin {{env "ROUTER_DEFAULT_SERVER_FIN_TIMEOUT" "1s"}}
+{{- else }}
+  timeout server-fin 1s
+{{- end }}
 {{- if (matchPattern "[1-9][0-9]*(us|ms|s|m|h|d)?" (env "ROUTER_SLOWLORIS_TIMEOUT" "")) }}
   timeout http-request {{env "ROUTER_SLOWLORIS_TIMEOUT" "10s" }}
 {{- else }}