Fixes previous commmit with bin/server (https://github.com/amber-smalltalk/amber/commit/3177a9da4d7317320431c266e4ac59cc48dabfa3#commitcomment-3143636)

bin/server

@@ -1,3 +1,3 @@
 #!/bin/bash
 cd `dirname $0`/..
-node ./cli/js/amber-cli.js $@
+node ./cli/js/amber-cli.js serve $@