BAC-243: clean up DefaultSettings.php

```
Linting app/includes/wikia/DefaultSettings.php...
243: includes/wikia/Module.php can not be found
266: includes/wikia/services/FacebookSharing.class.php can not be found
267: includes/wikia/services/TwitterSharing.class.php can not be found
268: includes/wikia/services/PlusoneSharing.class.php can not be found
269: includes/wikia/services/StumbleuponSharing.class.php can not be found
270: includes/wikia/services/RedditSharing.class.php can not be found
271: includes/wikia/services/EmailSharing.class.php can not be found
279: includes/wikia/services/VideoUsageService.php can not be found
332: skins/oasis/modules/footer/FooterMenuItemFactory.class.php can not be found
333: skins/oasis/modules/footer/FooterMenuItemBase.class.php can not be found
334: skins/oasis/modules/footer/features/FooterShareItem.class.php can not be found
335: skins/oasis/modules/footer/features/FooterFollowItem.class.php can not be found
336: skins/oasis/modules/footer/features/FooterMenuItem.class.php can not be found
337: skins/oasis/modules/footer/features/FooterLinkItem.class.php can not be found
338: skins/oasis/modules/footer/features/FooterHtmlItem.class.php can not be found
339: skins/oasis/modules/footer/features/FooterCustomizeItem.class.php can not be found
340: skins/oasis/modules/footer/features/FooterDevinfoItem.class.php can not be found
341: skins/oasis/modules/footer/features/FooterDisabledItem.class.php can not be found
347: includes/wikia/services/sass/SassSourceContext.class.php can not be found
348: includes/wikia/services/sass/SassException.class.php can not be found
349: includes/wikia/services/sass/Source/SassSource.class.php can not be found
350: includes/wikia/services/sass/Source/SassFileSource.class.php can not be found
351: includes/wikia/services/sass/Source/SassStringSource.class.php can not be found
352: includes/wikia/services/sass/Compiler/SassCompiler.class.php can not be found
353: includes/wikia/services/sass/Compiler/SassExternalRubyCompiler.class.php can not be found
354: includes/wikia/services/sass/Filter/SassFilter.class.php can not be found
355: includes/wikia/services/sass/Filter/SassFilterBase64.class.php can not be found
356: includes/wikia/services/sass/Filter/SassFilterCdnRewrite.class.php can not be found
357: includes/wikia/services/sass/Filter/SassFilterCssImports.class.php can not be found
358: includes/wikia/services/sass/Filter/SassFilterJanus.class.php can not be found
509: includes/wikia/Resources.php can not be found

Found 31 include(s) of missing files
```

Partially (SASS related files) covered by f3d2d8c