haskdogs.cabal: fix missing README

haskdogs.cabal

@@ -3,7 +3,7 @@
 -- http://www.haskell.org/cabal/release/cabal-latest/doc/users-guide/authors.html#pkg-descr.
 -- The name of the package.
 Name:                haskdogs
-Version:             0.3.1
+Version:             0.3.2
 Synopsis:            Generate ctags file for haskell project directory and it's deps
 Homepage:            http://github.com/ierton/haskdogs
 License:             BSD3
@@ -13,7 +13,7 @@ Maintainer:          ierton@gmail.com
 Category:            Development
 Build-type:          Simple
 Cabal-version:       >=1.6
-extra-source-files:  README
+extra-source-files:  README.md
 Description:
     haskdogs is a small shellscript-like tool which creates tag file for entire
     haskell project directory. It takes into account first-level dependencies by