Improve usage of Caching and Lazy Loading of the DbContext

[GeekInTheNorth]

• Previously Cached Resources:
  • Loading of CSP Settings
  • Loading of CORS Settings
  • Loading of fully compiled security headers
• Increase scope of caching to cover:
  • Loading of Legacy Security Response Headers
  • Loading of CSP Sandbox Settings
  • Loading of CSP Sources
• Consistently Lazy Load the DB Context to delay creation of Db Connections until they are needed.