chore(changelog): add support for to and from flags in changelog.js

This commit adds support for "--to=SHA" and "--from=SHA" when running
the script at scripts/publish/changelog.js to override defaults.

Fixes #2913

scripts/publish/changelog.js

@@ -2,8 +2,24 @@
 
 'use strict';
 
+/**
+ * Just a small command-line wrapper around the conventional-changelog npm module
+ * (https://www.npmjs.com/package/conventional-changelog), which also prepends
+ * changes to CHANGELOG.md.
+ *
+ * By default, this script will generate changes from relevant commits between the
+ * most recent tag and HEAD. The `from` and `to` flags may be provided to control the range of
+ * commits to process.
+ *
+ * Manually specify begin and end
+ * $ ./changelog.js --from=e987ac40343d89d47b7b6cc1c5932fd55b30e18a --to=3f7ebde037d92f8d93c6a40c0d73f840cac08287
+ * Run with default (latest tag...head)
+ * $ ./changelog.js
+ */
+
 var fs = require('fs');
 var cl = require('conventional-changelog');
+var args = require('minimist')(process.argv.slice(2));
 
 var changelogFile = 'CHANGELOG.md';
 
@@ -13,6 +29,14 @@ var config = {
   version: require('../../package.json').version
 };
 
+if (args.from) {
+  config.from = args.from;
+}
+
+if (args.to) {
+  config.to = args.to;
+}
+
 cl(config, function(err, log) {
   if (err) {
     console.error('Failed to generate changelog: ' + err);