set missing metadata fields, prepping alpha.2 (#5067)

* setting first batch of descriptions

* fix what I just broke

* next batch

* and pallets, too

* last batch

* set cargo.lock

* keep'em dev-deps

* bump version to alpha.2

substrate/utils/prometheus/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 description = "Prometheus exporter server"
 name = "prometheus-exporter"
-version = "0.8.0-alpha.1"
+version = "0.8.0-alpha.2"
 license = "GPL-3.0"
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"