Adding the Voltha missing manual

Change-Id: Ic6cc2e5ed80e04fb009809c9a2fca393e5dcabfd
diff --git a/docs/manuals/user/gitbook/styles/printable.css b/docs/manuals/user/gitbook/styles/printable.css
new file mode 100644
index 0000000..bb100ca
--- /dev/null
+++ b/docs/manuals/user/gitbook/styles/printable.css
@@ -0,0 +1,15 @@
+@media print {
+  .book-body {
+    left: 0px !important;
+  }
+  .book .book-body {
+    left: 0px !important;
+    overflow: visible !important;
+  }
+  div.book-summary {
+    display: none !important;
+  }
+  a.navigation-prev { display: none !important; }
+  a.navigation-next { display: none !important; }
+  div { page-break-inside: avoid; }
+}