Github source connector: Add some transforms to deal with the different possible events

[oscerd]

In Github connector while consuming, you can get a list of event of different type. Some of the objects have a payload too, so we should try to check what kind of payload we have an transform before putting the record value.

[oscerd]

The way the event consumer work in camel upstream has been changed a bit, now it will return the type of event, without the payload and just a subset of information as headers. So this is not needed anymore.