react-rust-postgres: add connection to postgres with migrations

Signed-off-by: Jérémie Drouet <jeremie.drouet@gmail.com>

react-rust-postgres/backend/Cargo.toml

@@ -7,12 +7,17 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+diesel_migrations = "1.4.0"
 rocket = "0.4.4"
 serde = "1.0"
 serde_json = "1.0"
 serde_derive = "1.0"
 
+[dependencies.diesel]
+version = "1.0.0"
+features = ["postgres"]
+
 [dependencies.rocket_contrib]
 version = "0.4.4"
 default-features = false
-features = ["json"]
+features = ["json", "diesel_postgres_pool"]