[+] add build commit, date to --version output, closes #256 (#258)

Author: pashagolub

Makefile

@@ -3,7 +3,7 @@ GOENV=CGO_ENABLED=0
 all: vip-manager
 
 vip-manager: *.go */*.go
-	$(GOENV) go build -ldflags="-s -w" .
+	$(GOENV) go build -ldflags="-s -w -X main.version=`git describe --tags --abbrev=0` -X main.commit=`git show -s --format=%H HEAD` -X main.date=`git show -s --format=%cI HEAD`" .
 
 install:
 	install -d $(DESTDIR)/usr/bin

main.go

@@ -20,7 +20,9 @@ import (
 
 var (
 	// vip-manager version definition
-	version = "2.4.0"
+	version = "master"
+	commit  = "none"
+	date    = "unknown"
 )
 
 func getMask(vip netip.Addr, mask int) net.IPMask {
@@ -48,6 +50,8 @@ func main() {
 		//			return nil, nil
 		//		}
 		fmt.Printf("version: %s\n", version)
+		fmt.Printf("commit:  %s\n", commit)
+		fmt.Printf("date:    %s\n", date)
 		return
 	}