Public API documentation fixes

Just formatting and documentation stuff

refs #4883

 * http/response.php
 * config.php
 * response.php
 * files.php
 * idbconnection.php
 * app.php
 * user.php
 * template.php
 * share.php
 * db.php
 * icache.php & il10n.php

cc @DeepDiver1975 @karlitschek 296 Errors right now ... hope it will decrease a lot :)