Started work on cli, which also meant adding setup.py

I'm using click, and click recommends using a setup.py - so I've added one of
those. I also refactored code into a new datasite package. It's not quite
deploying to now properly at the moment though - I seem to have messed up the
path handling a bit.

Also snuck in a new template for the "Row" view.

Refs #40

datasite/cli.py

@@ -0,0 +1,24 @@
+import click
+from .app import app, ensure_build_metadata
+
+@click.group()
+def cli():
+    """
+    Datasite!
+    """
+
+
+@cli.command()
+def build():
+    ensure_build_metadata(True)
+
+
+@cli.command()
+@click.argument('files', type=click.Path(exists=True), nargs=-1)
+@click.option('-h', '--host', default='0.0.0.0')
+@click.option('-p', '--port', default=8001)
+@click.option('--debug', is_flag=True)
+def serve(files, host, port, debug):
+    '''Serve up specified database files with a web UI'''
+    click.echo('Serve! files={} on port {}'.format(files, port))
+    app.run(host=host, port=port, debug=debug)