[#810, github-backed example][xl]: improve looks, improve README, rename from simple-example to github-backed (#864)

examples/github-backed-catalog/datasets.json

@@ -0,0 +1,44 @@
+[
+  {
+    "owner": "datasets",
+    "branch": "main",
+    "repo": "oil-prices",
+    "files": [
+      "data/brent-daily.csv",
+      "data/brent-monthly.csv",
+      "data/brent-weekly.csv",
+      "data/brent-year.csv",
+      "data/wti-daily.csv",
+      "data/wti-monthly.csv",
+      "data/wti-weekly.csv",
+      "data/wti-year.csv"
+    ],
+    "readme": "README.md"
+  },
+  {
+    "owner": "datasets",
+    "branch": "main",
+    "repo": "investor-flow-of-funds-us",
+    "files": [
+      "data/monthly.csv",
+      "data/weekly.csv"
+    ],
+    "readme": "README.md"
+  },
+  {
+    "owner": "fivethirtyeight",
+    "repo": "data",
+    "branch": "master",
+    "description": "Data about bad drivers",
+    "name": "Bad Drivers",
+    "files": ["bad-drivers/bad-drivers.csv"],
+    "readme": "bad-drivers/README.md"
+  },
+  {
+    "owner": "fivethirtyeight",
+    "repo": "data",
+    "branch": "master",
+    "files": ["nba-raptor/historical_RAPTOR_by_player.csv", "nba-raptor/historical_RAPTOR_by_team.csv"],
+    "readme": "nba-raptor/README.md"
+  }
+]