[DOCS] Updated links to the ES Ref for the X-Pack ref.
[DOCS] Updated links to the ES Ref for the X-Pack ref.

Original commit: elastic/x-pack-elasticsearch@d47f2766784f2a25e98407576a7f01893cf52339

nknize/elasticsearch,robin13/elasticsearch,coding0011/elasticsearch,scorpionvicky/elasticsearch,GlenRSmith/elasticsearch,strapdata/elassandra,vroyer/elassandra,GlenRSmith/elasticsearch,nknize/elasticsearch,HonzaKral/elasticsearch,robin13/elasticsearch,gfyoung/elasticsearch,gfyoung/elasticsearch,gingerwizard/elasticsearch,coding0011/elasticsearch,gingerwizard/elasticsearch,vroyer/elassandra,gingerwizard/elasticsearch,nknize/elasticsearch,nknize/elasticsearch,uschindler/elasticsearch,robin13/elasticsearch,gingerwizard/elasticsearch,strapdata/elassandra,coding0011/elasticsearch,uschindler/elasticsearch,HonzaKral/elasticsearch,scorpionvicky/elasticsearch,GlenRSmith/elasticsearch,scorpionvicky/elasticsearch,scorpionvicky/elasticsearch,strapdata/elassandra,coding0011/elasticsearch,robin13/elasticsearch,gingerwizard/elasticsearch,uschindler/elasticsearch,GlenRSmith/elasticsearch,uschindler/elasticsearch,gingerwizard/elasticsearch,vroyer/elassandra,coding0011/elasticsearch,scorpionvicky/elasticsearch,gfyoung/elasticsearch,HonzaKral/elasticsearch,gfyoung/elasticsearch,strapdata/elassandra,uschindler/elasticsearch,gfyoung/elasticsearch,gingerwizard/elasticsearch,GlenRSmith/elasticsearch,HonzaKral/elasticsearch,nknize/elasticsearch,robin13/elasticsearch,strapdata/elassandra