Merge pull request #24 from aavogt/master

#21 and a start at some doctest
Add OverloadedString language pragma
Add basic instructions on loading IHaskell files into ghci for the first time
Remove OverloadedString pragma
Edit README.md about OverloadedString pragma in .ghci
Merge pull request #26 from edechter/master

Add info about using GHCi with this package
formatting fixes for README
add `Description :` field for haddock

descriptions are copied from README mostly, but a couple
were missing from there
Add .ghci to repo and suggest the more reliable `cabal repl`