Use ENT_SUBSTITUTE when escaping
re #302 : Remove translator related methods

- Remove TemplateInterface::getTranslator
- Remove TemplateInterface::setTranslator
- Remove TemplateInterface::translate
- Remove TemplateInterface::choose
- Remove TemplateFilterInterface::translate
- Remove TemplateHelperInterface::translate
- Remove Date::getTranslator()
- Remove Date::setTranslator()