`data` object: wrap bem entity fields into `entity`.

[blond]

Actual data object:

{
     block: 'block',
     elem: 'elem',
     modName: 'mod',
     modVal: true,
     tech: 'tech',
     level: 'level',
     path: 'level/block__elem_mod'
}

Expected data object:

{
     entity: { block: 'block', elem: 'elem', modName: 'mod', modVal: true },
     tech: 'tech',
     level: 'level',
     path: 'level/block__elem_mod'
}

Often need to handle BEM entity. Now this knowledge is spread out in four fields, three of which are optional. How to detect type of BEM entity now:

var entity = { block: data.block },
    type;

data.elem && (entity.elem = data.elem);
data.modName && (entity.modName = data.modName);
data.modVal && (entity.modVal = data.modVal);

type = bemNaming.typeOf(entity);

How to make it easier:

var type = bemNaming.typeOf(data.entity);

[qfox]

This must be in readme imho. Doesn't it?