Add action-tracking information for Discovery/Parsing

[nothingface0]

• Probably create a new django application
• Will need new Model(s). Something like:
  • DataDiscoveryEvents?
    • action: what action was made (file_discovery, file_parsing)
    • accepted: boolean.
    • time_received: time that the action request was received.
    • time_started: time that the action started.
    • user: user who requested it.
    • result: The result of the action: number of histograms/files that were created/discovered? And FKs to which ones?