add flask sample

Signed-off-by: kouul <maulloohans@gmail.com>

flask/app/app.py

@@ -0,0 +1,9 @@
+from flask import Flask
+app = Flask(__name__)
+
+@app.route('/')
+def hello():
+	return "Hello World!"
+
+if __name__ == '__main__':
+	app.run(host='0.0.0.0')