ext42-appsdk-bump-app-catalog 52 bumping sdk to 115-a8db865

sdk commit: RallySoftware/appsdk@6f3c07177df226db66a6d0416740c23fe6161236
author: Rally Dev Pair
message: S48890 - Added DatePicker and updated DateField to support date ranges and fire aftervalidate event

sdk commit: RallySoftware/appsdk@a8db86593a01766452df13022fdbe389e0207323
author: Rally Dev Pair
message: DE18923: Kanban Board paging: fix doubling of wip during additional page loads