define the semantics and lifecycle of a containerized Application

[goern]

This issue aims to define the lifecycle of a multi container application.

A first working draft is at https://gist.github.com/goern/d8910ba7a10ff26bc8f2

it is related to

• https://github.com/projectatomic/atomicapp/issues/184
• https://github.com/projectatomic/atomicapp/issues/159
• https://github.com/projectatomic/atomicapp/issues/142