chore: Prepare 0.9.1 release (#1343)

* Update documentation url in cargo tomls

* Bump versions to 0.9.1

* Update guides

* Add prepare/publish scripts

* Update changelog

publish-release.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+# Script which automates publishing a crates.io release of the prost crates.
+
+set -ex
+
+if [ "$#" -ne 0 ]
+then
+  echo "Usage: $0"
+  exit 1
+fi
+
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+
+CRATES=( \
+  "tonic" \
+  "tonic-build" \
+  "tonic-types" \
+  "tonic-reflection" \
+  "tonic-health" \
+  "tonic-web" \
+)
+
+for CRATE in "${CRATES[@]}"; do
+  pushd "$DIR/$CRATE"
+
+  echo "Publishing $CRATE"
+
+  cargo publish
+
+  popd
+done