Add some missing copyright boilerplate

Language/Haskell/GhcMod/CustomPackageDb.hs

@@ -1,6 +1,20 @@
+-- ghc-mod: Making Haskell development *more* fun
+-- Copyright (C) 2015  Daniel Gröber <dxld ÄT darkboxed DOT org>
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero General Public License as published by
+-- the Free Software Foundation, either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU Affero General Public License for more details.
+--
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <http://www.gnu.org/licenses/>.
 module Language.Haskell.GhcMod.CustomPackageDb where
 
-
 import Control.Applicative
 import Control.Monad
 import Control.Category ((.))
@@ -11,7 +25,6 @@ import Language.Haskell.GhcMod.Monad.Types
 import Language.Haskell.GhcMod.PathsAndFiles
 import Prelude hiding ((.))
 
-
 parseCustomPackageDb :: String -> [GhcPkgDb]
 parseCustomPackageDb src = map parsePkgDb $ filter (not . null) $ lines src
  where