Fixed URLs based on the guidelines given in Jekyll documentation

As per documentation of Jekyll [here](http://jekyllrb.com/docs/github-pages/#project-page-url-structure):-

1. In `_config.yml`, set the `baseurl` option to `/project-name` – note the leading slash and the absence of a trailing slash.
2. When referencing JS or CSS files, do it like this: `{{ site.baseurl }}/path/to/css.css` – note the slash immediately following the variable (just before “path”).
3. When doing permalinks or internal links, do it like this: `{{ site.baseurl }}{{ post.url }}` – note that there is no slash between the two variables.
4. Finally, if you’d like to preview your site before committing/deploying using `jekyll serve`, be sure to pass an empty string to the `--baseurl` option, so that you can view everything at `localhost:4000` normally (without /project-name at the beginning): `jekyll serve --baseurl ''`

This way the sites will work with both URL styles - `/` and `/project`.