cabal2nix.cabal: release version 1.15
cabal2nix.cabal: release version 1.15

Fuuzetsu/cabal2nix,dmalikov/cabal2nix,spencerjanssen/cabal2nix,bennofs/cabal2nix,psibi/cabal2nix,jb55/cabal2nix,gridaphobe/cabal2nix