create wrapper for container.ring

[david415]

This container.ring wrapper should include an interface and an implementation to encapsulate the interface type assertions... In this way we can isolate these type assertions to this small section of code. It should help us not only simplify our code but also reduce the error prone nature of using these type assertions.

[david415]

we instead replaced usage of container.ring with our ring implementation... essentially identical except it uses a Reassembly struct attribute instead of an empty interface. This helps us clean the code up considerably.