huge refactoring of content and theme

- de-personalize the theme as much as possible, moving personal info into config.toml parameters
- extract hard-coded content out layouts and into actual /content (especially home page and all of its assets)
- include full text of posts in RSS feed (aka making the world a better place)
- use abstract layout for both video pages (/leo and /birthday)

assets/sass/pages/_videos.scss

@@ -0,0 +1,32 @@
+@charset "UTF-8";
+
+// Video Styles
+body#videos {
+  margin: 75px auto;
+  text-align: center;
+
+  p {
+    font-size: 0.85em;
+    line-height: 1.5em;
+    color: #777777;
+    margin: 0;
+    padding: 0 10px;
+  }
+
+  a {
+    font-weight: bold;
+  }
+
+  a#logo svg {
+    height: 48px;
+    width: 48px;
+    padding: 4px;
+    margin: 16px 0 8px 0;
+  }
+
+  video {
+    width: $responsive-width;
+    height: auto;
+    font-family: inherit;    // for subtitles
+  }
+}