Extended base blocks for SEO purposes

added the following blocks:
- head_title (inside title element)
- head_meta_robots
- head_meta_description
- head_meta_keywords
- head_meta_open_graph
- head_link_canonical
- head_link_favicon
- head_link_rss
Merge pull request #142 from Crease29/b-dev-ce

Extended base blocks for SEO purposes