Feature/http service

[just-at-uber]

Added

• MockDate library which helps mock javascript date with a fixed date so that when integrations tests are run, the date is locked when the tests start and finishes. The date will reset once test is complete.

Changed

• replaced $http with httpService so that services can access http as well as components and is consistent between the two.
• getQueryStringFromObject to filter out keys with null or undefined values.
• workflow component cleanup for fetching data
• workflow component now adds a ready class when all fetching is complete. This change ensures workflow integration tests are not leaking requests between tests by using the ready class to start the testing phase.

Removed

• $moment as this was not referenced anywhere in the code.