Build mock if not templates

[Andrew Abramov]

If no template need build bundle without xjst core. Instead of it need provide mocks.

This can be useful to build BEMHTML for run in browsers with depsByTech.

For BEMHTML apply method should always returns empty string:

BEMHTML.apply = function () { return ''; };

For BEMTREE apply method should always returns empty object:

BEMTREE.apply = function () { return Vow.resolve({}); };