Provide a swagger2 spec for the dynamic API

Related issue: #144

src/PostgREST/Config.hs

@@ -39,6 +39,7 @@ data AppConfig = AppConfig {
     configDatabase  :: String
   , configAnonRole  :: String
   , configSchema    :: String
+  , configHost      :: String
   , configPort      :: Int
   , configJwtSecret :: Secret
   , configPool      :: Int
@@ -51,6 +52,7 @@ argParser = AppConfig
   <$> argument str (help "(REQUIRED) database connection string, e.g. postgres://user:pass@host:port/db" <> metavar "DB_URL")
   <*> strOption    (long "anonymous"  <> short 'a' <> help "(REQUIRED) postgres role to use for non-authenticated requests" <> metavar "ROLE")
   <*> strOption    (long "schema"     <> short 's' <> help "schema to use for API routes" <> metavar "NAME" <> value "public" <> showDefault)
+  <*> pure "localhost"
   <*> option auto  (long "port"       <> short 'p' <> help "port number on which to run HTTP server" <> metavar "PORT" <> value 3000 <> showDefault)
   <*> (secret . cs <$>
       strOption    (long "jwt-secret" <> short 'j' <> help "secret used to encrypt and decrypt JWT tokens" <> metavar "SECRET" <> value "secret" <> showDefault))