This macro allows you to add variables to the url when an url already has variables.

As you might know you can add any key-value pair to an url and receive those variables as template variables in this form: <tmpl_var session.form.namekey> 

This however is not so handy if the url might already have a query string. For example if you receive the url from a template variable. 

Note: a two nice enhancement might be:

1. check voor an anchor in the url  and deal with that

2. check not only for a semicolon as seperator, but also for an ampersant.

usage:
       process ( [url],[key,value] )

       url

       The url of the current page or the page where you would like to go.  If no url is given, the url of the
       current page will be used.

       key

       key/value pairs kan be given to the macro. The amount of key/value pairs is only limited by the maximum
       length of a URL in general.