bootstrap.sh: Download .cabal files in addition to tarballs.
bootstrap.sh: Download .cabal files in addition to tarballs.

Fixes #3139. Fixes #3133.

sopvop/cabal,gbaz/cabal,Heather/cabal,sopvop/cabal,kolmodin/cabal,Heather/cabal,themoritz/cabal,bennofs/cabal,garetxe/cabal,thomie/cabal,headprogrammingczar/cabal,headprogrammingczar/cabal,garetxe/cabal,mydaum/cabal,bennofs/cabal,gbaz/cabal,thomie/cabal,kolmodin/cabal,themoritz/cabal,themoritz/cabal,mydaum/cabal,sopvop/cabal