code: private SiteRecord getSiteRecord(String siteKey) {
  		SiteRecord siteRecord = this.siteRecords.get(siteKey);
  		if (siteRecord == null) {
  			siteRecord = new SiteRecord(siteKey);
  			this.siteRecords.put(siteKey, siteRecord);
  		}
  		return siteRecord;
  	}
docs: Returns a site record for the site of the given name, creating a new one
  if it does not exist yet.
  
  @param siteKey
  the key of the site
  @return the suitable site record