add test to check stdout logger with different log level

simplify logrus interface

add example for logrus

tryout logrus

fix ci tests for having redeclared method in main package

skip test Program with interrupt signal

test prog with interrupt signal

example of using ctx with cancelling & deadline

add merge method to run sq in 4 go routines so that test takes shorter time

add sleep into sq to make sure sq runs everything inside 1 goroutine

add sq into pipeline

implement pipeline

use file for saving player score

add /league endpoint

embedding http.Handler into PlayerServer