- Added initial interface for the following classes
	- PSDeserializer
	- PSDevice
	- PSExperiment
	- PSFeature
	- PSLevelPackStructure
	- PSLevelStructure
	- PSPartner
- Made readonly the "instanceKey" property of Saltr class.
Merge branch 'master' of https://github.com/plexonic/saltr-ios-sdk

Conflicts:
	Saltr/PSSaltr.h
	Saltr/PSSaltr.m
- Merged conflicts.