Changes

I added some of the minor details [[User: elichak | elichak]] mentioned in the [[Talk:How_to_do_a_Hello_World_application_using_XULRunner | Hello World discussion]]. She helped find a lot of the little mistakes that I would have never found. Just to note one thing she mentionied, posting bat files which creates the directory tree automatically, this won't be a good idea for the guide. The main reason is that bat files are Window's specific. Until someone creates a script which auto-creates directories for Linux and Mac, I won't put the bat file but thanks for the help.