Currently, the Create Properties File wizard assumes that you don't already 
have an ant.properties file that you would like to associate with the build 
script. We should change this so that the property allows you to enter a file 
name, the ... opens the wizard, the first page of the wizard contains a file 
chooser where they can select the file and a New Properties File button if they 
want to create one.

I know that this is all much more laborious than just entering the one 
<property file="myproperties.ant.properties"/> tag directly in the source but 
if we're going to have the wizard we might as well make it support all the 
likely use cases.