change flask_app name code example

Example 1: flask how to run app

$ export FLASK_APP=hello.py
$ python -m flask run
 * Running on http://127.0.0.1:5000/

Example 2: flask commands

# manage.py

from flask_script import Manager

from myapp import app

manager = Manager(app)

@manager.command
def hello():
    print "hello"

if __name__ == "__main__":
    manager.run()