### Please read and mark the following check list before creating a pull request:

 - [] I read and followed the [CONTRIBUTING.md](https://github.com/akveo/nebular/blob/master/CONTRIBUTING.md) guide.
 - [] I read and followed the [New Feature Checklist](https://github.com/akveo/nebular/blob/master/DEV_DOCS.md#new-feature-checklist) guide.
 
 #### Short description of what this resolves: