Tests for the Swift REST API wrappers

## Expected Behavior

Same tests run for `SKY_api_*` functions shall be used for Swift API wrappers .

## Actual Behavior

No tests running in Travis

## Specifications

- Version: 0.25.0
- Platform: all
- Subsystem: all exported API sets

## Possible Solution

Reuse existing API test code in Travis script, if any, and parameterize the invocation to send requests to a services deployed at a given base URL .