Added old blog posts

I finally added my old blog posts.

I had to use a lot of regex magic to modify the frontmatter of each post (e.g. converting --- to +++), but now it is done, Zola was able to compile each post.

I think some links will be broken, because I changed some internal paths, but I think a not-so-lazy person can help themself.

If you find some broken links, typos or have some feedback, send me an email.