Add Learning Tools Interoperability (LTI) blade.

LTI blade allows to include LTI components to courses.
Python integration, Jasmine and acceptance tests are included.

common/lib/xmodule/xmodule/css/lti/lti.scss

@@ -0,0 +1,30 @@
+div.lti {
+    // align center
+    margin: 0 auto;
+
+    h3.error_message {
+        display: block;
+    }
+
+    form.ltiLaunchForm {
+        display: none;
+    }
+
+    iframe.ltiLaunchFrame {
+        width: 100%;
+        height: 800px;
+        display: none;
+        border: 0px;
+        overflow-x: hidden;
+    }
+
+    &.rendered {
+        iframe.ltiLaunchFrame {
+            display: block;
+        }
+
+        h3.error_message {
+            display: none;
+        }
+    }
+}