Show commit ID on version

Makefile

 OUTPUT_DIR = ./builds
-GIT_COMMIT = `git rev-parse HEAD`
+GIT_COMMIT = `git rev-parse HEAD | cut -c1-10`
+BUILD_OPTIONS = -ldflags "-X main.CommitID=$(GIT_COMMIT)"
 
-gotty: server/asset.go main.go server/*.go webtty/*.go backend/*.go
-	godep go build
+gotty: server/asset.go main.go server/*.go webtty/*.go backend/*.go Makefile
+	godep go build ${BUILD_OPTIONS}
 
 asset:  server/asset.go
 

main.go

@@ -18,7 +18,7 @@ import (
 func main() {
 	app := cli.NewApp()
 	app.Name = "gotty"
-	app.Version = Version
+	app.Version = Version + "+" + CommitID
 	app.Usage = "Share your terminal as a web application"
 	app.HideHelp = true
 	cli.AppHelpTemplate = helpTemplate

version.go

 package main
 
 var Version = "2.0.0-alpha"
+var CommitID = "unknown_commit"