moved into a class, so multiple frequencies can be created

[ferdinandyb]

Implementing it as a class rather than a module would allow to define multiple frequencies in parallel threads. The syntax need not change much.

Use case:

from cronus.beat import Beat
import time
import datetime
import threading

def do_some_work():
    beat = Beat()
    beat.set_rate(2)
    while beat.true():
        print (datetime.datetime.now(), "doing work")
        beat.sleep()
        
def do_some_work2():
    beat = Beat()
    beat.set_rate(10)
    while beat.true():
        print (datetime.datetime.now(), "doing work2")
        beat.sleep()
if __name__ == "__main__":

    t1 = threading.Thread(target = do_some_work)
    t2 = threading.Thread(target = do_some_work2)
    t1.start()
    t2.start()
    t1.join()