Use of hardcoded tmp file instead of recommended file_cache_path

These are throughout the repository but I'm only including the following example for brevity. Is there a reason we're using hardcoded tmp files instead of file_cache_path? This is probably only an issue when there isn't a log of room on /tmp but nonetheless, should probably be updated.

Check the example out at https://github.com/engineyard/ey-cloud-recipes/blob/master/cookbooks/elasticsearch/recipes/default.rb#L22