[kepler-dev] Configuration.configurations()

[Christopher Brooks]

I added a static method to Configuration:

    /** Return a list of all the configurations that have been created.
     *  Note  that if this method is called before a configuration
     *  is created, then it will return an empty linked list.
     *  @param A list of configurations, where each element of the list
     *  is of type Configuration.
     */
    public static List configurations() {
        return _configurations;
    }

I also updated the class comment of Configuration with the
some of the info below.

Edward wrote:
> I think the "please don't show..." could be handled even with the
> current preferences mechanism...  Configuration has a static field that
> lists all the configuration that have been created (in principle, there
> could be more than one).  We could provide
> a static method to access this list. This access would have to
> happen after the Configuration is created, of course.
> 
> To access the configuration from a random place, if you have a NamedObj,
> then you can call Configuration.findEffigy().  This is a static method.
> Then call Effigy.toplevel(). The result will always be the configuration.
> 
> However, we need to be careful about creating dependencies on GUI
> infrastructure. 

_Christopher