Hacks of Core:

includes/bootstrap.inc
function drupal_settings_initialize()
 * UNL change: include a "global" settings file that applies to all sites.

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sites/all/modules/drush/commands/core/drupal/site_install_7.inc
function drush_core_site_install_version()
 * UNL change! Setting this to FALSE because we don't want them and they're hard coded.

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rewrite.php
used to allow public files to be accessed without the sites/<site_dir>/files prefix

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