Goal: 

Add more developer documentation around what happens during introspection and snapshotting. These documents should exist in the backend repo, under "/docs/workflows/". Mostly likely, one document for introspection and one document for snapshot.

For introspection, the documentation should include the following information

• What is introspection?
• When does introspection happen?
• What happens when a repository is introspected? e.g. calls yummy and yummy parses the repomd.xml, primary.xml, etc. 
• What is the significance of introspecting a repository? How is the introspected metadata used? How does image builder use introspected repositories?
• How does introspection differ from snapshotting?

For snapshots, the documentation should include the following information

• What is a snapshot?
• When does snapshotting happen?
• What happens when a repository is snapshotted?
• What happens in pulp when a repository is snapshotted? Include information about the pulp workflow like remotes, syncing, repository versions, publications, distributions, etc. Consider what API calls are made to pulp and what someone would need to know to understand what those calls do.
• How are snapshots used? How does image builder use snapshots?
• How does snapshotting different from introspecting?

Acceptance Criteria:

• There are new documents that answer all the questions listed above such that a new developer can understand the introspection and snapshot workflows.