Make AbuseFilter's examine table legible with a dark theme

Currently, the ext.abuseFilter.css module used by the extension enforces colorization from Wikipedia, which makes for hard-to-read examine tables if the wiki has a dark theme&mdash;see example at http://codfanfic.wikia.com/wiki/Special:AbuseFilter/examine/36819 . This change resets the styling if the Oasis theme is dark.