Create textarea as separate block (close #1033)

I've made only basics yet: `common`+`desktop`, `BEMHTML`-templates, js, styles only for `islands` theme.
I didn't remove `input_type_textarea` to have ability to compare new block with it.
The maxlength attribute is supported in Internet Explorer 10+, Firefox, Opera 15+, Chrome, and Safari.

Note: The maxlength attribute of the <textarea> tag is not supported in Internet Explorer 9 and earlier versions, or in Opera 12 and earlier versions.