Separate lib and exe; add languageDir setting

app/Main.hs

@@ -0,0 +1,26 @@
+module Main where
+
+import qualified Data.Text as T
+
+import Options.Applicative
+
+import Myriad
+
+data Args = Args
+    { configInput :: T.Text
+    }
+
+parseArgs :: IO Args
+parseArgs = execParser $ info (helper <*> args) (fullDesc <> progDesc "Run the Myriad server")
+    where
+        args = Args <$> option str (mconcat
+            [ long "config"
+            , short 'c'
+            , help "Sets the Dhall configuration"
+            , metavar "DHALL"
+            ])
+
+main :: IO ()
+main = do
+    Args { configInput } <- parseArgs
+    runMyriadServer configInput