update cabal-install. Issue tonymorris#22

tonymorris · tonymorris · commit 4e45e96af979 · 2013-11-25T15:48:46.000+10:00
diff --git a/README.markdown b/README.markdown
@@ -115,6 +115,7 @@ satisfied all tests with cabal-install and doctest. From the base directory of
 this source code:
 
     > cabal update
+    > cabal install cabal-install
     > cabal install doctest
     > cabal install QuickCheck
     > cabal configure --enable-tests
