Adapting «throwable» inits.
Adapting «throwable» inits.

- Defined custom `ConfigurationErrors`
- Addapted to new `JSONSerializable` throwable init
- Silenced compiler warnings for `throwable` inits.

drewcrawford/XcodeServerSDK,colemancda/XcodeServerSDK,colemancda/XcodeServerSDK,cojoj/XcodeServerSDK,czechboy0/XcodeServerSDK,cojoj/XcodeServerSDK,colemancda/XcodeServerSDK,drewcrawford/XcodeServerSDK,drewcrawford/XcodeServerSDK,czechboy0/XcodeServerSDK