David Monllaó authored Apr 03, 2019 and Eloy Lafuente committed Apr 09, 2019

- Removed redundant query to analytics_predict_samples
- Analysers API now uses recordsets to iterate through the analysable
  elements. They take the last analysed time into account.
- New method for targets so there is no need to always update the last
  analysis time. Useful for lightweight targets.