removed the old Android app

Running git-annex linux builds in termux seems to work well enough that the
only reason to keep the Android app would be to support Android 4-5, which
the old Android app supported, and which I don't know if the termux method
works on (although I see no reason why it would not).
According to [1], Android 4-5 remains on around 29% of devices, down from
51% one year ago.

[1] https://www.statista.com/statistics/271774/share-of-android-platforms-on-mobile-devices-with-android-os/

This is a rather large commit, but mostly very straightfoward removal of
android ifdefs and patches and associated cruft.

Also, removed support for building with very old ghc < 8.0.1, and with
yesod < 1.4.3, and without concurrent-output, which were only being used
by the cross build.

Some documentation specific to the Android app (screenshots etc) needs
to be updated still.

This commit was sponsored by Brett Eisenberg on Patreon.

Types/DesktopNotify.hs

@@ -10,9 +10,7 @@
 module Types.DesktopNotify where
 
 import Data.Monoid
-#if MIN_VERSION_base(4,9,0)
 import qualified Data.Semigroup as Sem
-#endif
 import Prelude
 
 data DesktopNotify = DesktopNotify
@@ -21,22 +19,14 @@ data DesktopNotify = DesktopNotify
 	}
 	deriving (Show)
 
-appendDesktopNotify :: DesktopNotify -> DesktopNotify -> DesktopNotify
-appendDesktopNotify (DesktopNotify s1 f1) (DesktopNotify s2 f2) =
-	DesktopNotify (s1 || s2) (f1 || f2)
-
-#if MIN_VERSION_base(4,9,0)
 instance Sem.Semigroup DesktopNotify where
-	(<>) = appendDesktopNotify
-#endif
+	(DesktopNotify s1 f1) <> (DesktopNotify s2 f2) =
+		DesktopNotify (s1 || s2) (f1 || f2)
 
 instance Monoid DesktopNotify where
 	mempty = DesktopNotify False False
-#if MIN_VERSION_base(4,11,0)
-#elif MIN_VERSION_base(4,9,0)
+#if ! MIN_VERSION_base(4,11,0)
 	mappend = (Sem.<>)
-#else
-	mappend = appendDesktopNotify
 #endif
 
 mkNotifyStart :: DesktopNotify

Types/Difference.hs

@@ -26,9 +26,7 @@ import qualified Git.Config
 import Data.Maybe
 import Data.Monoid
 import qualified Data.Set as S
-#if MIN_VERSION_base(4,9,0)
 import qualified Data.Semigroup as Sem
-#endif
 import Prelude
 
 -- Describes differences from the v5 repository format.
@@ -80,18 +78,13 @@ appendDifferences a@(Differences {}) b@(Differences {}) = a
 	}
 appendDifferences _ _ = UnknownDifferences
 
-#if MIN_VERSION_base(4,9,0)
 instance Sem.Semigroup Differences where
 	(<>) = appendDifferences
-#endif
 
 instance Monoid Differences where
 	mempty = Differences False False False
-#if MIN_VERSION_base(4,11,0)
-#elif MIN_VERSION_base(4,9,0)
+#if ! MIN_VERSION_base(4,11,0)
 	mappend = (Sem.<>)
-#else
-	mappend = appendDifferences
 #endif
 
 readDifferences :: String -> Differences

Types/Messages.hs

@@ -5,16 +5,12 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
-{-# LANGUAGE CPP #-}
-
 module Types.Messages where
 
 import qualified Utility.Aeson as Aeson
 
 import Control.Concurrent
-#ifdef WITH_CONCURRENTOUTPUT
 import System.Console.Regions (ConsoleRegion)
-#endif
 
 data OutputType = NormalOutput | QuietOutput | JSONOutput JSONOptions
 	deriving (Show)
@@ -40,10 +36,8 @@ data MessageState = MessageState
 	, concurrentOutputEnabled :: Bool
 	, sideActionBlock :: SideActionBlock
 	, implicitMessages :: Bool
-#ifdef WITH_CONCURRENTOUTPUT
 	, consoleRegion :: Maybe ConsoleRegion
 	, consoleRegionErrFlag :: Bool
-#endif
 	, jsonBuffer :: Maybe Aeson.Object
 	, promptLock :: MVar () -- left full when not prompting
 	}
@@ -56,10 +50,8 @@ newMessageState = do
 		, concurrentOutputEnabled = False
 		, sideActionBlock = NoBlock
 		, implicitMessages = True 
-#ifdef WITH_CONCURRENTOUTPUT
 		, consoleRegion = Nothing
 		, consoleRegionErrFlag = False
-#endif
 		, jsonBuffer = Nothing
 		, promptLock = promptlock
 		}

Types/Test.hs

@@ -11,9 +11,7 @@ module Types.Test where
 
 import Test.Tasty.Options
 import Data.Monoid
-#if MIN_VERSION_base(4,9,0)
 import qualified Data.Semigroup as Sem
-#endif
 import Prelude
 
 import Types.Command
@@ -25,25 +23,17 @@ data TestOptions = TestOptions
 	, internalData :: CmdParams
 	}
 
-appendTestOptions :: TestOptions -> TestOptions -> TestOptions
-appendTestOptions a b = TestOptions
-	(tastyOptionSet a <> tastyOptionSet b)
-	(keepFailuresOption a || keepFailuresOption b)
-	(fakeSsh a || fakeSsh b)
-	(internalData a <> internalData b)
-
-#if MIN_VERSION_base(4,9,0)
 instance Sem.Semigroup TestOptions where
-	(<>) = appendTestOptions
-#endif
+	a <> b = TestOptions
+		(tastyOptionSet a <> tastyOptionSet b)
+		(keepFailuresOption a || keepFailuresOption b)
+		(fakeSsh a || fakeSsh b)
+		(internalData a <> internalData b)
 
 instance Monoid TestOptions where
 	mempty = TestOptions mempty False False mempty
-#if MIN_VERSION_base(4,11,0)
-#elif MIN_VERSION_base(4,9,0)
+#if ! MIN_VERSION_base(4,11,0)
 	mappend = (Sem.<>)
-#else
-	mappend = appendTestOptions
 #endif
 
 type TestRunner = TestOptions -> IO ()