Move gh-pages branch files into /docs and add test files

- Jekyll ignore `/docs` and `/test` folders when using from root
- Update Staticman config to point to correct branch and data file location
- Replace `{{ base_path }}` references with `absolute_url` filter
- Update documentation

test/_posts/2010-08-05-post-image-standard.md

@@ -0,0 +1,44 @@
+---
+title: "Post: Image (Standard)"
+categories:
+  - Post Formats
+tags:
+  - image
+  - Post Formats
+---
+
+The preferred way of using images is placing them in the `/assets/images/` directory and referencing them with an absolute path. Prepending the filename with `{% raw %}{{ site.url }}{{ site.baseurl }}/assets/images/{% endraw %}` will make sure your images display properly in feeds and such.
+
+Standard image with no width modifier classes applied.
+
+**HTML:**
+
+```html
+{% raw %}<img src="{{ site.url }}{{ site.baseurl }}/assets/images/filename.jpg" alt="">{% endraw %}
+```
+
+**or Kramdown:**
+
+```markdown
+{% raw %}![alt]({{ site.url }}{{ site.baseurl }}/assets/images/filename.jpg){% endraw %}
+```
+
+![Unsplash image 9]({{ site.url }}{{ site.baseurl }}/assets/images/unsplash-image-9.jpg)
+
+Image that fills page content container by adding the `.full` class with:
+
+**HTML:**
+
+```html
+{% raw %}<img src="{{ site.url }}{{ site.baseurl }}/assets/images/filename.jpg" alt="" class="full">{% endraw %}
+```
+
+**or Kramdown:**
+
+```markdown
+{% raw %}![alt]({{ site.url }}{{ site.baseurl }}/assets/images/filename.jpg)
+{: .full}{% endraw %}
+```
+
+![Unsplash image 10]({{ site.url }}{{ site.baseurl }}/assets/images/unsplash-image-10.jpg)
+{: .full}