* Add Go Client (Worker) Implementation (#133)

* Worker interfaces in Go

* Move external dependency of httpclient inside package (#135)

Http Client

* * Add optional tasks
* Fix for taskId not getting replaced for simple tasks in task input calculation
* License headers for go client

* fixed the sink name

* gradle updates (#147)

* 1.7.1 (#151)

* capture the event payload in the task's output

* prefix the internal events with conductor when using dynamic event names

* Update queue name

* add more details to action processor and workflow executor

* more details and streamlined key names

* do not add policies if empty

* * allow referencing more task  parameters in input/outputs
* Unit tests

* handle null

* minor changes and code cleanup