EMI-3 WN, DPM_disk and BDII with Yum based SPMA

Hi,

  These are the changes we made to allow installation/upgrade of EMI-3 WNs, DPM_disk, BDII_top and BDII_site nodes without disrupting other nodes on the same cluster using old package lists.

  We "select" the alternate package lists by setting the following variables:

variable QUATTOR_SPMA_YUM ?= true;
variable RPMS_SUFFIX ?= '-yd';

  This also adds some new DPM HTTP / WebDAV configuration templates.

  Cheers,
  Victor