Modifications to make this script work under Linux/*BSD

* `date' command in Linux/BSD lacks the `-v' flag; work around
  this by using  `-d "1 day ago"'
  (thanks to
  http://www.masaokitamura.com/2009/02/17/how-to-get-yesterdays-
  date-using-bash-shell-scripting/)
* mysqld (on at least my Centos box) requires a configuration change
  and the `--local-infile=1' command to allow it to load data from
  the locally downloaded file
* added a configurable location for the log file (most linux/*bsd
  boxen don't have $HOME/Library/Logs)
Added note to README about sales-only accounts working
Add notes to README about the other options