Reviving the Blog

This is related to issues github/gitscm-next#13 and github/gitscm-next#83

The blog feature might not be 100% ready, just wanted to get some early feedback...

Blog entries are visible again.Also made some small changes to the blog structure.

We can keep adding blog posts by just adding .markdown or .html files to the app/view/blog/posts directory (it was blog/progit before).

the index for blog posts needs some design :heart: