considerDIVs

Hi, Vadim:

I've saw your codes about **considerDIVs**, and actually, i am working on this issue days, and find that not all the pages are using 'P' tag to wrap their article content, so **considerDIVs** is really necessary.

but my thought was little difference from your:
- node-read must consider all candidates that match *divToPElementsRe* if client user needed, so, i add an optional setting named *considerDIVs*, and it's value default as true, usage:

  ```read([URL], { considerDIVs: false}, function(err, article){...})```
- the implementation way reference to Arc90's: turn all divs that don't have children block level elements into p's, including the matched Ps and TEXT node.

- **TEST**

  i've test it on thousands pages from *msn.com.cn*, *21cn.com*, *sina.com*, *163.com*, *cnbeta.com*...

if you think its feasible, or have any idea, or it can not work on some specified pages, just tell me, let's work on this together.

thx!!!