CLC-4566 - CalCentral in iOS *web-app* mode forces user to log back in every time you switch apps

https://jira.ets.berkeley.edu/jira/browse/CLC-4566
Merge pull request #3170 from christianv/CLC-4566

CLC-4566 - CalCentral in iOS *web-app* mode forces user to log back in every time you switch apps