changed doc html layout to alabaster

- make page width 100% of the window
- decrease code font size (seems to big compared to other text)

Change-Id: Id36dffea22163dcbd77303b0aab8c852371ef017

doc/source/_static/custom.css

@@ -1,4 +1,35 @@
+/* this is for the sphinx_rtd_theme
 div.wy-nav-content
 {
 	    max-width: 100% !important;
 }
+*/
+div.body {
+    max-width: 100%;
+}
+
+div.bodywrapper {
+    margin: 0 0 0 26%;
+}
+
+div.sphinxsidebar {
+    width: 25%;
+}
+
+pre, tt, code {
+    font-size: 0.75em;
+}
+
+@media screen and (max-width: 875px) {
+    div.bodywrapper {
+        margin: 0;
+    }
+    div.sphinxsidebar {
+        width: 102.5%;
+    }
+    div.document {
+        width: 100%;
+    }
+}
+
+