Follow-up work on USDA connector. And other code maintenance.
Some code maintenance of old connectors.
Updated SerpentAPI connector, removed extra remote server request that improves the execution time. And other code maintenance.
Merge remote-tracking branch 'upstream3/master'
DATA-1248 Code maintenance for FishWisePro connector.
Merge remote-tracking branch 'upstream3/master'
Merge pull request #29 from eliagbayani/master

Code maintenance of old connectors and follow-up work on USDA connector.