check for required params
shared singleton access
restructure properties in the source code for better readability
added doc.
added tests
xcode proj update.
changed device token config param to NSData
deployment target set to 5.0
remove not needed responseObject
response.json not needed any more
comply with the API change of registerWithClientInfo:
xcode proj update
Merge branch 'AGPUSH-48.client-sdk'