Add support for 'ctr' style model that computes cliktrhough rates Add noise_scale parameter that applies laplace noise to every numerical output in the model Bug 1968369 - Add noise to ohttp merino request, ctr support for inferred newtab personalization r=reviewer [...details if needed...] Original Revision: https://phabricator.services.mozilla.com/D251087 Differential Revision: https://phabricator.services.mozilla.com/D252857