👷 Add a watch task without server

Fix #1

gulpfile.babel.js

@@ -30,6 +30,10 @@ gulp.task('build',
 gulp.task('default',
   gulp.series('build', server, watch));
 
+// Build emails, run the server, and watch for file changes
+gulp.task('watch',
+  gulp.series('build', watch));
+
 // Build emails, then send to litmus
 gulp.task('litmus',
   gulp.series('build', creds, aws, litmus));

package.json

@@ -7,6 +7,7 @@
   "scripts": {
     "start": "gulp",
     "build": "gulp --production",
+    "watch": "gulp watch --production",
     "zip": "gulp zip --production",
     "litmus": "gulp litmus --production",
     "mail": "gulp mail --production"