Added a number of new features and remove API key references

2.8.0

There are a number of new features and changes in this release so will move to version 2.8.
The most important one from a breaking change point of view is that the use of API keys is no longer allowed.
You should now be using Access Tokens to access the API
For more information on any of the changes please see the README.
We have added examples for all of the new features

Remove API Key references (#230)

API Keys are no longer valid. We now use Acces tokens.
So removing reference to use API keys in the SDK

Add support for snooze (#236)

Added appropriate code to be able to snooze conversation and to read the conversation model for snooze attributes

Add conversation ratings (#235)

Add extra code to support reading conversation ratings

Add support for marking conversation as read (#234)

Add ability to make a conversation as read

Add support for display_as when finding conversation (#239)

Add a new find that allows extra parameters

Support running assignment rules (#243)

Build support for recent API feature to allow running assignment rules on a conversation
https://developers.intercom.com/intercom-api-reference/reference#run-conversation-assignment-rules

Support Event Summaries (#244)

List event summaries of a user
https://developers.intercom.com/intercom-api-reference/reference#view-user-events-summaries

Extract Iterator implementation into TypedDataCollection (#247)

First thing, TypedDataCollection now implements Iterator, it is delegating the hasNext(), next() and remove() methods to a TypedDataCollectionIterator instance.
Second, I have removed all specific implementations of Iterator from all Collection classes, which were just copy-paste.

Update webhook topics and add ping (#245)

Added support for more topics

Allow parsing of responses from DELETE requests (#248)

Now we check if DELETE response has data if it does proceed to process it as any other normal data
If there is no data just return null