Add a script to generate contributor list.

Signed-off-by: Daniel Nephin <dnephin@docker.com>

script/release/contributors

@@ -0,0 +1,27 @@
+#!/bin/bash
+set -e
+
+
+function usage() {
+    >&2 cat << EOM
+Print the list of github contributors for the release
+
+Usage:
+
+    $0 <previous release tag>
+EOM
+    exit 1
+}
+
+[[ -n "$1" ]] || usage
+PREV_RELEASE=$1
+VERSION=HEAD
+URL="https://api.github.com/repos/docker/compose/compare"
+
+curl -sf "$URL/$PREV_RELEASE...$VERSION" | \
+    jq -r '.commits[].author.login' | \
+    sort | \
+    uniq -c | \
+    sort -nr | \
+    awk '{print "@"$2","}' | \
+    xargs echo