Add .ghci to repo and suggest the more reliable `cabal repl`

.ghci

+:set -package ghc
+:set -package ghc-paths
+:set -optP-include -optPdist/build/autogen/cabal_macros.h
+:set -XOverloadedStrings

README.md

@@ -100,18 +100,8 @@ cabal build
 ```
 
 Loading IHaskell into GHCi for testing:
-If you want to play around with IHaskell by loading it into GHCi, you need to include the ghc package and the cabal macros file. cabal_macros.h is generated by the ```cabal build``` command and the file is placed in the build directory. You will also need to use the OverloadedStrings language extension. So if you are at the top level of the IHaskell project, you can load GHCi as follows: 
-```bash
-ghci -XOverloadedStrings -package ghc -optP-include -optPdist/build/autogen/cabal_macros.h
-```
-
-or you can create a .ghci file in the top level directory, like so: 
-
-```bash
-# In the IHaskell .ghci file
-:set -package ghc
-:set -package ghc-paths
-:set -optP-include -optPdist/build/autogen/cabal_macros.h
-:set -XOverloadedStrings
-```
-
+If you are at the top level of the IHaskell project, you can load GHCi with
+`cabal repl` or `ghci`. The first option hides all packages not listed in the
+`IHaskell.cabal`, while the second option only sets a couple options given in
+the `.ghci` file in the repo.  Once in ghci, it can then be useful to `:load
+*IHaskell/Config` or similar.