[log_accel] Minor refactoring.

Unless I am misunderstanding the intention behind the equation:

    (A - D)/C - (B - D)/C = (A - B)/C

The output seems to be exactly the same:

    Before:
    =======
     1m7s000│Nov 11 06:45:01 XXX-XXX CRON[28452]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    11m7s000│Nov 11 06:55:01 XXX-XXX CRON[28819]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    21m7s000│Nov 11 07:05:01 XXX-XXX CRON[29186]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    31m7s000│Nov 11 07:15:01 XXX-XXX CRON[29552]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    33m7s000│Nov 11 07:17:01 XXX-XXX CRON[29629]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
    41m7s000│Nov 11 07:25:01 XXX-XXX CRON[29922]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    51m7s000│Nov 11 07:35:01 XXX-XXX CRON[30290]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
   1h1m7s000│Nov 11 07:45:01 XXX-XXX CRON[30657]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)

    After:
    ======
     1m7s000│Nov 11 06:45:01 XXX-XXX CRON[28452]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    11m7s000│Nov 11 06:55:01 XXX-XXX CRON[28819]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    21m7s000│Nov 11 07:05:01 XXX-XXX CRON[29186]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    31m7s000│Nov 11 07:15:01 XXX-XXX CRON[29552]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    33m7s000│Nov 11 07:17:01 XXX-XXX CRON[29629]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
    41m7s000│Nov 11 07:25:01 XXX-XXX CRON[29922]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    51m7s000│Nov 11 07:35:01 XXX-XXX CRON[30290]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
   1h1m7s000│Nov 11 07:45:01 XXX-XXX CRON[30657]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)

Some names and identifying details in the log snippets above have been changed
to protect the privacy of individuals. Any resemblance to actual computers,
sentient or otherwisei, is purely coincidental.
Merge pull request #119 from sureshsundriyal/master

[log_accel] Minor refactoring.