Use the heap size set in Chef via /etc/default/elasticsearch
Use the heap size set in Chef via /etc/default/elasticsearch

Closes: #170

nbudin/cookbook-elasticsearch,spuder/cookbook-elasticsearch,gouketsu/cookbook-elasticsearch,spuder/cookbook-elasticsearch,GemHQ/cookbook-elasticsearch,nbudin/cookbook-elasticsearch,spuder/cookbook-elasticsearch,zzugg/cookbook-elasticsearch,zzugg/cookbook-elasticsearch,zzugg/cookbook-elasticsearch,nbudin/cookbook-elasticsearch,gouketsu/cookbook-elasticsearch,gouketsu/cookbook-elasticsearch