Delete class modal from body of compoennt.php of protostar template

There is no sense to have this class on the body. `&tmpl=component` is used usually to display content without extra formatting. But there is a special formating on `.modal` class. Here is how send main form looks in `<iframe>`.

![pr1](https://f.cloud.github.com/assets/650741/820501/502f89ca-efc6-11e2-9545-b0ae7725891a.png)

And here how it looks without modal class.

![pr2](https://f.cloud.github.com/assets/650741/820502/504e3b0e-efc6-11e2-9c22-20c90181d479.png)

The main idea is that if I want borders on the body or some other styles I can always connect my own CSS. And `component` should have minimalistic view.