[WiP] rename project from Caravel to Superset (#1576)

* Change in files

* Renamin files and folders

* cleaning up a single piece of lint

* Removing boat picture from docs

* add superset word mark

* Update rename note in docs

* Fixing images

* Pinning datatables

* Fixing issues with mapbox-gl

* Forgot to rename one file

* Linting

* v0.13.0

* adding pyyaml to dev-reqs

superset/assets/visualizations/sankey.css

@@ -0,0 +1,33 @@
+.sankey .node rect {
+  cursor: move;
+  fill-opacity: .9;
+  shape-rendering: crispEdges;
+}
+
+.sankey .node text {
+  pointer-events: none;
+  text-shadow: 0 1px 0 #fff;
+}
+
+.sankey .link {
+  fill: none;
+  stroke: #000;
+  stroke-opacity: .2;
+}
+
+.sankey .link:hover {
+  stroke-opacity: .5;
+}
+
+.sankey-tooltip {
+  position: absolute;
+  width: auto;
+  background: #ddd;
+  padding: 10px;
+  font-size: 12px;
+  font-weight: 200;
+  color: #333;
+  border: 1px solid #fff;
+  text-align: center;
+  pointer-events: none;
+}