Update some resources to be proper singletons.
Update some resources to be proper singletons.

The way singleton resources work changed in Djblets. The resources in
Review Board needed to be updated to account for this. Now, instead of
declaring name and name_plural to be the same, we set singleton to True.

chazy/reviewboard,Khan/reviewboard,sgallagher/reviewboard,davidt/reviewboard,chazy/reviewboard,davidt/reviewboard,1tush/reviewboard,bkochendorfer/reviewboard,beol/reviewboard,atagar/ReviewBoard,atagar/ReviewBoard,brennie/reviewboard,chipx86/reviewboard,1tush/reviewboard,beol/reviewboard,custode/reviewboard,KnowNo/reviewboard,1tush/reviewboard,chazy/reviewboard,1tush/reviewboard,Khan/reviewboard,1tush/reviewboard,custode/reviewboard,1tush/reviewboard,beol/reviewboard,custode/reviewboard,davidt/reviewboard,brennie/reviewboard,davidt/reviewboard,reviewboard/reviewboard,sgallagher/reviewboard,1tush/reviewboard,KnowNo/reviewboard,KnowNo/reviewboard,1tush/reviewboard,1tush/reviewboard,reviewboard/reviewboard,atagar/ReviewBoard,atagar/ReviewBoard,Khan/reviewboard,atagar/ReviewBoard,chipx86/reviewboard,chazy/reviewboard,atagar/ReviewBoard,custode/reviewboard,Khan/reviewboard,bkochendorfer/reviewboard,reviewboard/reviewboard,atagar/ReviewBoard,sgallagher/reviewboard,KnowNo/reviewboard,chazy/reviewboard,chazy/reviewboard,atagar/ReviewBoard,Khan/reviewboard,Khan/reviewboard,bkochendorfer/reviewboard,chazy/reviewboard,Khan/reviewboard,chazy/reviewboard,beol/reviewboard,bkochendorfer/reviewboard,brennie/reviewboard,chazy/reviewboard,Khan/reviewboard,chipx86/reviewboard,chipx86/reviewboard,reviewboard/reviewboard,atagar/ReviewBoard,brennie/reviewboard,Khan/reviewboard,sgallagher/reviewboard