Stable version 0.4.1

This is purely a bugfix bump because I botched the
0.4.0 cabal file and subsequent Hackage release :|

ShellCheck.cabal

@@ -1,5 +1,5 @@
 Name:             ShellCheck
-Version:          0.4.0
+Version:          0.4.1
 Synopsis:         Shell script analysis tool
 License:          GPL-3
 License-file:     LICENSE
@@ -53,6 +53,10 @@ library
       ShellCheck.Checker
       ShellCheck.Data
       ShellCheck.Formatter.Format
+      ShellCheck.Formatter.CheckStyle
+      ShellCheck.Formatter.GCC
+      ShellCheck.Formatter.JSON
+      ShellCheck.Formatter.TTY
       ShellCheck.Interface
       ShellCheck.Parser
       ShellCheck.Regex