fix(Gruntfile): When compiling Compass, the Jade files was deleted and non-compiled, now it is fixed.
feat(filter): create generator for a new filter.

Example:

```bash
yo angularjs:filter myFilter
```
feat(app): Refactored prompts order and replaced engines value questions with checkboxes.
feat(service): added service generator.
docs(filter): Added filter usage guide to README.md
Release 0.3.0