appsdk-bump-app-catalog 423 bumping sdk to 1877-51a59e3

sdk commit: RallySoftware/appsdk@c7add66f6be8e7863074b74d2d7b11fee222fb00
author: Steven Boles
message: S63616 Hyperlink for email in rich text fields

sdk commit: RallySoftware/appsdk@51a59e3feea7536d320060dd308f62986b672467
author: Steven Boles
message: S63983 - refactored save indicator to use css3 transitions