Registration/Reset via Decorators

[BenjamenMeyer]

Enable something like the following:

@stackinabox.register(HelloService(), MyOtherService())
def my_test(...)
     ...

or

def services()
    a = my_service_a()
    b = my_dependent_service(a)
    return [a, b]

@stackinabox.register(services())
def my_test(...)
    ...

In the first case, multiple services could be easily added if they were not interdependent on each other.
In the second case, the function can setup interdependent services that utilize each other and return them as a group to be registered in a single call.

[BenjamenMeyer]

#45 enables the first case in the description; it also provides the ability for the test function to get access to the services via dictionary provided as a keyword parameter. Theoretically the test function should then be able to inter-connect the services as necessary.

I'll have to think about adding detection of the second portion - essentially, analyzing the *args or **kwars for an iterable object, and then ensuring that everything in the iterable is an instance of StackInABoxService, only then could the iterable be consumed as the services.

[BenjamenMeyer]

PR #56 adds support for generators and iterable objectss so I think we can close this out now