[NFR]Fix #1679

See #1679, add new param local for Phalcon\Tag::linkTo.

```php
echo Phalcon\Tag::linkTo('http://phalconphp.com/en/', 'Phalcon Home', FALSE);
echo Phalcon\Tag::linkTo('mailto:dreamsxin@gmail.com', 'dreamsxin@gmail.com', FALSE);
```
output:
`<a href="<a href="http://phalconphp.com/en/">Phalcon Home</a>`
`<a href="mailto:dreamsxin@gmail.com">dreamsxin@gmail.com</a>`