The site object provides site related properties and
      methods.
    Properties
- description
 - The displayable description of the site.
 - isPublic
 - Whether the site is public or not (true or false).
 - node
 - The site node (null if there are none).
 - shortName
 - A read-only unique short name identifying the site.
 - siteGroup
 - The site group name.
 - sitePermissionGroups
 - A map of role name mapped to associated group name.
 - sitePreset
 - A read-only name of the site preset used to create the site.
 - title
 - The displayable title of the site.
 - visibility
 - The visibility of the site (PUBLIC_SITE, MODERATED_SITE, PRIVATE_SITE)
 
Example
    var site = siteService.getSite("simple-site");
    if(site){
        
        model.sitePreset = site.sitePreset;
        model.shortName = site.shortName;
        model.title = site.title;
        model.description = site.description;
        model.isPublic = site.isPublic;
        model.visibility = site.visibility;
        model.node = site.node;
        model.siteGroup = site.siteGroup;
        model.sitePermissionGroups = site.sitePermissionGroups;
        model.customProperties = site.customProperties;
    }