MINOR: http-check: Remove support for headers/body in "option httpchk" version

This trick is deprecated since the health-check refactoring, It is now
invalid. It means the following line will trigger an error during the
configuration parsing:

  option httpchk OPTIONS * HTTP/1.1\r\nHost:\ www

It must be replaced by:

  option httpchk OPTIONS * HTTP/1.1
  http-check send hdr Host www
5 files changed