Most work has been already done by @maoe in terms of the #12 pull request
This fix depends on a few yet unreleased ghc74-fixed libraries (see also https://gist.github.com/1496342 for the current GHC-7.4 status)
Eliminate warnings and errors on GHC 7.2
Eliminate warnings on GHC 7.2
Add -fcontext-stack=30 flag to scion-server
This flag will be needed by upcoming atto-lisp.
Add backward compatibility for GHC < 7.2
Relax dependency on attoparsec
Relax various library dependencies to support GHC-7.4.0
No code changes were necessary to be able to compile it with GHC-7.4.0 as it
already compiles with GHC-7.2.x thanks to Mitsutoshi Aoe's work on that.