Update bower.json per latest changes

- Replace docs-assets with docs
- Remove dependencies property as there aren't dependencies
Improve _config.yml

- Properly indent values
- Add missing comments
Trim trailing spaces.
Remove default type for css and move the font before any scripts.
Use html5shiv from OSSCSN and add respond.js for older browsers media queries.
Losslessly compress images.

Before: 5,71 MB (5.989.547 bytes)
After:  3,83 MB (4.027.029 bytes)
Merge pull request #301 from ZDroid/config-yml-indent

Improve `_config.yml`
Merge pull request #299 from ZDroid/bower-json

Update bower.json per latest changes