Improved safety atop.daily

[GermanAizek]

Reasons create this PR changes

• Substitution of variables without quotation marks
  In shell scripts, $PIDFILE and $LOGPATH are sometimes used without quotes, which is dangerous for paths with spaces or special characters

• Executing external commands with substitution
  The use of ps -p 'cat $PIDFILE' and similar constructions (kill 'cat $PIDFILE') is dangerous if there is no verification of the contents of the PID file (for example, if the file is tampered with by an attacker)

• Without checking the expandable path, it potentially allows you to delete files outside the destination area if variables are substituted

• Before using the contents of the PIDFILE, make sure that it contains only numbers.

• Instead of rm {} use -- and quoting