4.2.0

• Bump version to 4.2.0
• [NT-459] Qualtrics Surveys (#1000)
• [NT-645] Adding category_id and removing rewards and updates counts (#1002)
• [NT-645] More tweaks to property names and cleanup (#998)
• Prepare Data Lake tracking request with authentication headers (#997)
• [NT-707] Naming changes and white-listing clean events (#995)
• [NT-645] Clean user properties & session properties (#990)
• [NT-688] Project events & properties clean up (#985)
• [NT-687] "Tab Bar Clicked" Event (#988)
• [NT-645] Clean discovery properties & events [Part 1] (#984)
• [NT-685] Abstract TrackingClient to be configurable (#983)
• [NT-649] Errored pledges query (#981)
• [NT-669, NT-496] Shimmer Loading Extension (#980)
• [NT-627] "View rewards" when a project has ended (#979)
• [NT-623] “View rewards” for non-live projects (#978)
• [NT-643] Remove 1Password extension (#976)
• [NT-450] Deprecate iOS 11 (#904)
• [NT-545] Transition from thanks page to project page (#977)