patch applied (cabal): Move the license check from a sanity check to a QA check

[Duncan Coutts]

Sun Jan 20 16:17:22 PST 2008  Duncan Coutts <duncan at haskell.org>
  * Move the license check from a sanity check to a QA check
  Also extend the check. It's now a QA error to use a license that is empty
  or AllRightsReserved. It's a warning to not specify a license file. It's an
  error for the license file to be given but not exist.
  Note that QA errors are not fatal for generating tarballs. But they will become
  fatal errors for uploading to the public hackage server. It will still be
  possible to use AllRightsReserved or another license on a private hackagedb.

    M ./Distribution/PackageDescription.hs -4 +1
    M ./Distribution/PackageDescription/QA.hs -5 +13