Title: ESX / agent_vsphere: Now able to re-use session cookies
Level: 1
Component: checks
Compatible: compat
Version: 1.2.7i3
Date: 1437571627
Class: feature

The agent_vsphere now reuses the session cookie as long as possible.
This prevents large amounts of Logon/Logoff messages in the vCenter log.

Whenever the cookie gets invalid the agent starts from the beginning, carries out
a normal login and refreshes the outdated cookie.
