Some more changes

README.md: Removed crontab instructions.
	   Added runner.sh usage and some more notes
cpu_parser.py: If the not run properly the script
	       should exit with error code
runner.sh: Get load every 5 seconds. Modelate sleep
	   time inside runner script and not via crontab

Signed-off-by: Ema <emma.ciobanu@gmail.com>