Making Drupal Framework Install not fail when a mail system doesn't exist

By setting send mail to true for the one command, we are circumventing drupal
install from failing because there is no way to set the mail system before
install however, drupal does send an email to the site administrator in order
to let them know that a new version is ready of drupal.
Merge pull request #1 from generalredneck/mail_fix

Making Drupal Framework Install not fail when a mail system doesn't exist