DOC: peers: clarify when entry expiration date is renewed.

This patch add some details to know which rules are updating
the expiration timer of an entry.

It also adds a comment to know how to fetch a value without renewing
this timer.

This patch addresses github issue #615

This patch should be backported on all still supported branches

(cherry picked from commit 423ed389ac04f586d62cc185ff3e022e171d0612)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 9e8f894cab2dca0611e65c51d79812d9f3ef7987)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
1 file changed