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

docs/_sass/_animations.scss

@@ -0,0 +1,21 @@
+/* ==========================================================================
+   ANIMATIONS
+   ========================================================================== */
+
+@-webkit-keyframes intro {
+  0% {
+    opacity: 0;
+  }
+  100% {
+    opacity: 1;
+  }
+}
+
+@keyframes intro {
+  0% {
+    opacity: 0;
+  }
+  100% {
+    opacity: 1;
+  }
+}