make IntercomClient methods protected

[cosmastech]

Why?

I think private visibility of the IntercomClient methods is a hinderance.

In a project I am working on, I need to decorate the handleResponse() method so that it checks for errors returned in the response (and possibly updates cache), but right now, the only way to do this is to duplicate code from base IntercomClient class (and not just a little bit, pretty much all of it).

How?

sets all private methods to protected visibility.