Moving images and static folders

Images now included relative to the `docs/source` folder instead of the rst file.
Also makes sure to add the updated `yosyshq.css` (which as a sidenote has ended up as `custom.css` in most of the other docs).

docs/source/_static/custom.css

@@ -0,0 +1,15 @@
+/* Reduce whitespace in cmd def pages */
+.cmd.def .highlight-yoscrypt, .cmd.def .highlight pre {
+    padding: 0%;
+    margin: 0%;
+}
+
+.cmd.def .highlight-none, .cmd.def .highlight pre {
+    padding-top: 0%;
+    margin-top: 0%;
+}
+
+/* Make images full width */
+.width-helper {
+    max-width: 100%;
+}  

docs/source/_static/yosyshq.css

@@ -0,0 +1,26 @@
+/* Don't hide the right sidebar as we're placing our fixed links there */
+aside.no-toc {
+    display: block !important;
+}
+
+/* Colorful headings */
+h1 {
+    color: var(--color-brand-primary);
+  }
+  
+h2, h3, h4, h5, h6 {
+    color: var(--color-brand-content);
+}
+
+/* Use a different color for external links */
+a.external {
+    color: var(--color-brand-primary) !important;
+}
+
+.wy-table-responsive table td {
+    white-space: normal;
+}
+  
+th {
+    text-align: left;
+}