Data persistence between requests

[BenjamenMeyer]

StackInABox is designed to only last for the length of a test. Loaded into StackInAWSGI that likely means that the data in a normal StackInABox model would be destroyed between requests or at a minimum not reliably retrieved. To handle this StackInAWSGI needs to be able to have a type of session that can be created using the admin functionality. The session maintains the StackInABox services for itself, and should keep all the data alive until the session is closed.

Note: Normally the session is the thread in a normal unit test scenario. Here we need to make it part of the WSGI scenario.

• Session to manage a StackInABox instance
  • create a Session object to manage sessions
  • create a session
  • remove a session
  • keep the session alive between WSGI requests
• Ability to create a StackInABox instance from scratch when creating a session
  • instantiate a session-specific StackInABox instance
  • instantiate the various StackInABoxServices for the session

[BenjamenMeyer]

PR #9 does most of this, but we need to confirm that the sessions remain alive between WSGI requests.

[BenjamenMeyer]

Data remains alive between calls and sessions are persistent but limited to supporting a single worker. Issue #15 is tracking that last bit.