Added feature:
* added additional method which allow to change client identifier and catchup on subscribed channels
* copied library into demo projects
* updated library information (debug output in console)
Enhancements:
* tweaked client identifier logic change in a way, which will allow to send all presence events and still be able to catchup
* copied library into demo projects
* updated library information (debug output in console)
Fixed issue:
* fixed wrong state flag which prevented catchup to go in correct way

Tweaked:
* added proper handling of error, which may occur during client identifier update
* copied library into demo projects
* updated library information (debug output in console)
Merge branch 'origin/feature-t181'

Conflicts:
	cocoa/HOWTO/ClientSidePresence/PubNubMacOSTestApplication/libs/PubNub/Core/PubNub.m
	cocoa/HOWTO/SimpleSubscribe/PubNubMacOSTestApplication/libs/PubNub/Core/PubNub.m
	cocoa/PubNubMacOSTestApplication/PubNubMacOSTestApplication/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/APNSVideo/demo9/demo9/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/CallsWithoutBlocks/CallsWithoutBlocks/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/ClientSidePresence/PubNubDemo/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/HelloWorld/pubnubDemoExample/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/SimpleSubscribe/PubNubDemo/libs/PubNub/Core/PubNub.m
	iOS/HOWTO/ULSMethods/ULSMethods/libs/PubNub/Core/PubNub.m
	iOS/iPadDemoApp/pubnub/libs/PubNub/Core/PubNub.m
	iOS/tests/ConnectionIssues/pubnub/libs/PubNub/Core/PubNub.m
	iOS/tests/PubNubTestBackground/pubnub/libs/PubNub/Core/PubNub.m
	iOS/tests/iOSUnitTests/pubnub/libs/PubNub/Core/PubNub.m
	iOS/tests/pubnubBackground/pubnubBackground/libs/PubNub/Core/PubNub.m