Vapor: 4.36.0 Release

This patch was authored and released by @Mordil.

As reported by #2480, right now SessionData is a public type without much use to developers to write middleware, algorithms, etc. on top of due to how strongly the storage is encapsulated.

SessionData has been changed as follows:

• Now conforms to Equatable and ExpressibleByDictionaryLiteral
• A new snapshot computed property is available to get a copy of its storage
• init(_:) is now deprecated in favor of init(initialData:)

let data: SessionData = ["name": "Vapor"]
// creates a copy of the data as of this point
let snapshot = data.snapshot
client.storeUsingDictionary(snapshot)