jQuery-Ajax-Queue is a simple plugin that allows you to queue either 
the ajax calls in the order that you pass them to the queue or queue
the callbacks so they execute in order but the ajax requests themselves are 
executed asap.

Basic Use:
Works just like $.ajax() in jQuery http://api.jquery.com/jQuery.ajax/
except that you use $.ajaxQueue()

You can pass 3 parameters.
The first parameter is required.  It will be a JSON object formatted with all
the usual jQuery options.

The second is optional (unless you also want to change the mode) and defines a 
queue name.  It will default to 'ajax' as the queue name.  This is so you 
can have multiple queues and it might be a good idea to always set this.

The third is optional.  If it is set to the string 'sync' then each request 
will be sent to the server in the order they are called.  Each request will
sent after the previous ajax call completes.  It is like you made a sychronous
request to the server except that your javascript will keep executing from the
point where $.ajaxQueue was called.  If this param is set to 'async', it will 
send all the requests to the server as soon as $.ajaxQueue is called but the
callbacks will all execute in the order that the calls were made.

Credits:
Thanks to the jQuery Community for all that they have helped to create.
Thanks to elevenHuang via github for his fix to execute the original complete callback.