PROPOSAL: Add openFileTemplate, openBinaryFileTemplate to System.IO

Hi all, This is Add openFileTemplate, openBinaryFileTemplate to System.IO http://hackage.haskell.org/trac/ghc/ticket/3393 (originally part of http://hackage.haskell.org/trac/ghc/ticket/2610) In System.IO, openTempFile and openBinaryTempFile mask the file permissions of the file they create with 0o600. However, we would like to use it for implementing things like writeFileAtomic, in which case we want the default file permissions to be used. I propose that we add openFileTemplate and openBinaryFileTemplate functions, which use the default permissions. Deadline: 8th August (2 weeks). Thanks Ian