Changes for compatibility with ghc-7.10-rc2

2 modules: Name clashes caused by Applicative-Monad change in Prelude
2 modules: Ambiguities caused by Foldable/Traversable in Prelude
2 modules: Backwards incompatible changes in time-1.5 for defaultTimeLocale
9 modules: {-# LANGUAGE FlexibleContexts #-} (because GHC checks inferred types
           now, in addition to explicitly given type signatures)

Also silenced warnings about tab characters in source files.

src/compiler/GF/Server.hs

@@ -16,7 +16,11 @@ import GF.System.Directory(doesDirectoryExist,doesFileExist,createDirectory,
                            getDirectoryContents,removeFile,removeDirectory,
                            getModificationTime)
 import Data.Time (getCurrentTime,formatTime)
+#if MIN_VERSION_time(1,5,0)
+import Data.Time.Format(defaultTimeLocale,rfc822DateFormat)
+#else
 import System.Locale(defaultTimeLocale,rfc822DateFormat)
+#endif
 import System.FilePath(dropExtension,takeExtension,takeFileName,takeDirectory,
                        (</>),makeRelative)
 #ifndef mingw32_HOST_OS