Update Global Settings

@mdaines-r7 (@defndaines) Can you check this PR out? I'd like to get it merged for some automated tests I'm working on right now.
> I'm not a fan of this

Do any alternatives that come to mind?

> where a method on the Connection simply redirects to a load method. 

I'm not a fan of the load methods in general since you need to pass around a connection object. It doesn't follow [the SRP](http://en.wikipedia.org/wiki/Single_responsibility_principle) (all object need to know how to serialize/de-serialize themselves).

I based this method of of `Nexpose::Connection#sites` which returns an array of sites (rather site summaries) which are also configurable.