refactor cli and gui wrapper code. Details:

- all cli functions shared between ethereum and ethereal abstracted to utils/ cmd.go (should be ethcommon or shared or sth)
- simplify main() now readable stepwise
- rename main wrapper files to main.go
- rename commmand line args definition file from config.go to flags.go
- rename Do -> Start to parallel option names
- register interrupt for rpc server stop
- fix interrupt stopping js repl and ethereum
- register interrupt for mining stop
- custom config file option from command line
- debug option from command line
- loglevel option from command line
- changed ethutil.Config API
- default datadir and default config file set together with other flag defaults in wrappers
- default assetpath set together with other command line flags defaults in gui wrapper (not in ethutil.Config or ui/ui_lib)
- options precedence: default < config file < environment variables < command line

ethereal/flags.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"flag"
+)
+
+var Identifier string
+var StartRpc bool
+var RpcPort int
+var UseUPnP bool
+var OutboundPort string
+var ShowGenesis bool
+var AddPeer string
+var MaxPeer int
+var GenAddr bool
+var UseSeed bool
+var ImportKey string
+var ExportKey bool
+var NonInteractive bool
+var Datadir string
+var LogFile string
+var ConfigFile string
+var DebugFile string
+var LogLevel int
+
+// flags specific to gui client
+var AssetPath string
+
+func defaultAssetPath() string {
+	var assetPath string
+	// If the current working directory is the go-ethereum dir
+	// assume a debug build and use the source directory as
+	// asset directory.
+	pwd, _ := os.Getwd()
+	if pwd == path.Join(os.Getenv("GOPATH"), "src", "github.com", "ethereum", "go-ethereum", "ethereal") {
+		assetPath = path.Join(pwd, "assets")
+	} else {
+		switch runtime.GOOS {
+		case "darwin":
+			// Get Binary Directory
+			exedir, _ := osext.ExecutableFolder()
+			assetPath = filepath.Join(exedir, "../Resources")
+		case "linux":
+			assetPath = "/usr/share/ethereal"
+		case "window":
+			fallthrough
+		default:
+			assetPath = "."
+		}
+	}
+	return assetPath
+}
+
+func defaultDataDir() string {
+  usr, _ := user.Current()
+  return path.Join(usr.HomeDir, ".ethereum")
+}
+
+var defaultConfigFile = path.Join(defaultDataDir(), "conf.ini")
+
+func Init() {
+	flag.StringVar(&Identifier, "id", "", "Custom client identifier")
+	flag.StringVar(&OutboundPort, "port", "30303", "listening port")
+	flag.BoolVar(&UseUPnP, "upnp", false, "enable UPnP support")
+	flag.IntVar(&MaxPeer, "maxpeer", 10, "maximum desired peers")
+	flag.IntVar(&RpcPort, "rpcport", 8080, "port to start json-rpc server on")
+	flag.BoolVar(&StartRpc, "rpc", false, "start rpc server")
+	flag.BoolVar(&NonInteractive, "y", false, "non-interactive mode (say yes to confirmations)")
+	flag.BoolVar(&UseSeed, "seed", true, "seed peers")
+	flag.BoolVar(&GenAddr, "genaddr", false, "create a new priv/pub key")
+	flag.BoolVar(&ExportKey, "export", false, "export private key")
+	flag.StringVar(&LogFile, "logfile", "", "log file (defaults to standard output)")
+	flag.StringVar(&ImportKey, "import", "", "imports the given private key (hex)")
+	flag.StringVar(&Datadir, "datadir", defaultDataDir(), "specifies the datadir to use")
+	flag.StringVar(&ConfigFile, "conf", defaultConfigFile, "config file")
+	flag.StringVar(&DebugFile, "debug", "", "debug file (no debugging if not set)")
+	flag.IntVar(&LogLevel, "loglevel", int(ethlog.InfoLevel), "loglevel: 0-4: silent,error,warn,info,debug)")
+	flag.StringVar(&AssetPath, "asset_path", defaultAssetPath, "absolute path to GUI assets directory")
+
+	flag.Parse()
+}