Upgrade dependencies

Author: Mark-Simulacrum

Cargo.lock

@@ -7,11 +7,11 @@ edition = "2018"
 [dependencies]
 chrono = "0.4.6"
 anyhow = "1"
-handlebars = "1.0.3"
+handlebars = "3"
 env_logger = "0.7"
 log = { version = "0.4.5", features = ["serde"] }
 rustup-available-packages = { path = "../library/" }
 serde = { version = "1", features = [ "derive" ] }
 serde_yaml = "0.8"
 serde_json = "1"
-structopt = "0.2.10"
+structopt = "0.3"