Use the new ExtensionFinder to find static files in extensions.
Use the new ExtensionFinder to find static files in extensions.

This just adds the new ExtensionFinder in Djblets to the list of static
file finders, so that extension-bundled static/ directories will be
searched.

1tush/reviewboard,beol/reviewboard,KnowNo/reviewboard,davidt/reviewboard,sgallagher/reviewboard,1tush/reviewboard,bkochendorfer/reviewboard,custode/reviewboard,chipx86/reviewboard,chipx86/reviewboard,davidt/reviewboard,1tush/reviewboard,bkochendorfer/reviewboard,brennie/reviewboard,davidt/reviewboard,reviewboard/reviewboard,1tush/reviewboard,beol/reviewboard,KnowNo/reviewboard,beol/reviewboard,custode/reviewboard,bkochendorfer/reviewboard,KnowNo/reviewboard,reviewboard/reviewboard,reviewboard/reviewboard,chipx86/reviewboard,brennie/reviewboard,davidt/reviewboard,beol/reviewboard,brennie/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard,sgallagher/reviewboard,1tush/reviewboard,sgallagher/reviewboard,custode/reviewboard,reviewboard/reviewboard,sgallagher/reviewboard,1tush/reviewboard,1tush/reviewboard,1tush/reviewboard,chipx86/reviewboard,custode/reviewboard,brennie/reviewboard,KnowNo/reviewboard