code: public Set<String> getApprovedTransKeys(String appid, String langCode) {
  		HashSet<String> approvedTransKeys = new HashSet<>();
  		if (StringUtils.isBlank(langCode)) {
  			return approvedTransKeys;
  		}
  
  		for (Map.Entry<String, String> entry : readLanguage(appid, langCode).entrySet()) {
  			if (!getDefaultLanguage(appid).get(entry.getKey()).equals(entry.getValue())) {
  				approvedTransKeys.add(entry.getKey());
  			}
  		}
  		return approvedTransKeys;
  	}
docs: Returns the set of all approved translations.
  @param appid appid name of the {@link com.erudika.para.core.App}
  @param langCode the 2-letter language code
  @return a set of keys for approved translations