Update and Migrate Diesel to 2.0

Almost have tag support working, still figuring out how to get photo
tags.

Cargo.toml

@@ -19,7 +19,8 @@ futures = "0.3.5"
 jsonwebtoken = "7.2.0"
 serde = "1"
 serde_json = "1"
-diesel = { version = "1.4.8", features = ["sqlite"] }
+diesel = { version = "2.0.2", features = ["sqlite"] }
+diesel_migrations = "2.0.0"
 hmac = "0.11"
 sha2 = "0.9"
 chrono = "0.4"