Support compare content

[latot]

Actually the lib does not have a way to compare the content, eq will return False to two parsed objects even if they have the same content.

Would be good be able to have comparison functions, ideally two of them:

• Compare if the content represent the same html
• Compare strictly if has the same data

The main different on them would be like compare

<div>
</div>

And

<div><div>

Both represent the same html, but has different data.