Use lens instead of uniplate
Use GHC.Generics instead of derive on GHC 7.8
Remove dummyGet and dummyPut from Yi.Utils
Remove list from Yi.Utils
Remove singleton from Yi.Utils
Remove ghc dependency from yi.cabal
Remove unneeded CPP pragma in Data.Rope
Don't use StandaloneDeriving in Yi.Buffer.Basic
Fix build on travis
Use lens in Yi.Buffer.Region
Merge pull request #548 from fread2281/cleanup

Misc Cleanup
Depend on binary 0.7 on >= GHC 7.8

While this isn’t needed (GHC 7.8 ships with binary 0.7, we indirectly
depend on GHC), it’s more correct and might just prevent future
headache.
Use Proxy in Yi.MiniBuffer
Replace (un)lines' and (map,on)Lines with an iso