Reimplement -datadir flag. Implements #79

The config file is actually loaded from the folder that datadir points at

ethereal/config.go

@@ -20,6 +20,8 @@ var ImportKey string
 var ExportKey bool
 var AssetPath string
 
+var Datadir string
+
 func Init() {
 	flag.StringVar(&Identifier, "id", "", "Custom client identifier")
 	flag.StringVar(&OutboundPort, "port", "30303", "listening port")
@@ -35,5 +37,7 @@ func Init() {
 	flag.BoolVar(&ExportKey, "export", false, "export private key")
 	flag.StringVar(&ImportKey, "import", "", "imports the given private key (hex)")
 
+	flag.StringVar(&Datadir, "datadir", ".ethereal", "specifies the datadir to use. Takes precedence over config file.")
+
 	flag.Parse()
 }

ethereal/ethereum.go

@@ -43,14 +43,14 @@ func main() {
 	ethchain.InitFees()
 
 	g, err := globalconf.NewWithOptions(&globalconf.Options{
-		Filename: path.Join(ethutil.ApplicationFolder(".ethereal"), "conf.ini"),
+		Filename: path.Join(ethutil.ApplicationFolder(Datadir), "conf.ini"),
 	})
 	if err != nil {
 		fmt.Println(err)
 	} else {
 		g.ParseAll()
 	}
-	ethutil.ReadConfig(".ethereal", ethutil.LogFile|ethutil.LogStd, g, Identifier)
+	ethutil.ReadConfig(Datadir, ethutil.LogFile|ethutil.LogStd, g, Identifier)
 
 	// Instantiated a eth stack
 	ethereum, err := eth.New(eth.CapDefault, UseUPnP)

ethereum/config.go

@@ -24,6 +24,8 @@ var NonInteractive bool
 var StartJsConsole bool
 var InputFile string
 
+var Datadir string
+
 func Init() {
 	flag.Usage = func() {
 		fmt.Fprintf(os.Stderr, "%s [options] [filename]:\n", os.Args[0])
@@ -46,6 +48,8 @@ func Init() {
 	flag.StringVar(&LogFile, "logfile", "", "log file (defaults to standard output)")
 	flag.StringVar(&ImportKey, "import", "", "imports the given private key (hex)")
 
+	flag.StringVar(&Datadir, "datadir", ".ethereum", "specifies the datadir to use. Takes precedence over config file.")
+
 	flag.Parse()
 
 	InputFile = flag.Arg(0)

ethereum/ethereum.go

@@ -62,14 +62,14 @@ func main() {
 	}
 
 	g, err := globalconf.NewWithOptions(&globalconf.Options{
-		Filename: path.Join(ethutil.ApplicationFolder(".ethereum"), "conf.ini"),
+		Filename: path.Join(ethutil.ApplicationFolder(Datadir), "conf.ini"),
 	})
 	if err != nil {
 		fmt.Println(err)
 	} else {
 		g.ParseAll()
 	}
-	ethutil.ReadConfig(".ethereum", lt, g, Identifier)
+	ethutil.ReadConfig(Datadir, lt, g, Identifier)
 
 	logger := ethutil.Config.Log