Product API should return more attributes by default

[jmiranda]

Product API only returns four basic properties. Need to add all first-level attributes to JSON.

curl -b cookies.txt -X GET -H "Accept: application/json" \
-H "Content-Type: application/json" \
https://openboxes.ngrok.io/openboxes/api/products/10001

{"data":{"id":"10001","productCode":"10001","name":"Mask, Oxygen, Nonrebreather, Pediatric","description":null}}

Any new associations should be added as separate endpoints.