deps: Context of deps declaration by techs

[veged]

Right now we must write like this:
b__e_m_v.deps.js

{ tech: 'js', mustDeps: { tech: 'bemhtml', block: 'b', elem: 'e', mods: { m: 'v' } }  }

It's strange, because we already have BEM-item context and it's possible to write:

{ tech: 'js', mustDeps: { tech: 'bemhtml' }  }

[arikon]

@SevInf Have a look at this, please. We can make it in 0.6.x.

[dfilatov]

Это нужно портировать в соответствующую v2-технологию.

[arikon]

@SevInf Серёг, портируй, пожалуйста