feature(style): expressions in style tags

Request Type: feature

How to reproduce: 

Component(s): $compile

Impact: small

Complexity: small

This issue is related to: 

**Detailed Description:**

Data-binding for style tag doesn't work (see style.js, terminal:true). Setting terminal to false in the directive will enable data-binding. Test provided.

**Other Comments:**

Enable data-binding for style tags

closes #2387