Update quickstart_dense.py URL in README
`wget https://github.com/TileDB-Inc/TileDB-Py/blob/dev/examples/quickstart_dense.py' pulls
the rich github web page. We should update this to the raw file URL:
@@ -32,7 +32,7 @@ This may take a while, as the pip package will automatically download and build
Next, save the `quickstart program <https://github.com/TileDB-Inc/TileDB-Py/blob/dev/examples/quickstart_dense.py>`_ into a file and run it::
- $ wget https://github.com/TileDB-Inc/TileDB-Py/blob/dev/examples/quickstart_dense.py
+ $ wget https://raw.githubusercontent.com/TileDB-Inc/TileDB-Py/dev/examples/quickstart_dense.py
$ python quickstart_dense.py
[[2 3 4]
[6 7 8]]
