Add Restkit to project configuration

[christiancompton]

This PR addresses some problems with the project.

• When upgrading to the Watson 1.0 SDK, RestKit was added as its own framework - this adds it automatically to the .xcproj
• Cleaning of log/print statements
• Swift 4.2 conversion

[christiancompton]

I'm seeing the app crash shortly after starting - I'll try to investigate the threading, but that may be out of scope for this PR.

[stevemar]

This is a good start, thanks for letting us know about the legacy api_key authentication being removed. If you can't figure out why the app crashes we'll re-evaluate if it's an issue with this change or if it's happening in master.

[christiancompton]

@stevemart This crash is happening in master. Back in April, I was attributing this error to the old processor on the iPhone 6S I was using, but I have access to an iPhone X now, and was able to replicate. Can you have someone investigate this?

[stevemar]

@christiancompton thanks for confirming it happens on master.

@sanjeevghimire can you look into this?

@christiancompton think we should merge your changes anyway or will that just make things harder to debug 🤔 ?

[christiancompton]

I am finishing some of the error logging improvements still - should be done shortly.

[stevemar]

thanks!