Added additional build details

Makefile

@@ -18,6 +18,17 @@ GO_FILES := $(shell find . -name '*.go' | grep -v /vendor/ | grep -v '*_test.go'
 GO_TEST_FILES := $(shell find . -name '*_test.go' -type f | rev | cut -d "/" -f2- | rev | sort -u)
 GO_BUILD_FILES := $(shell find . -name 'main.go')
 
+VERSION := `git describe --tags`
+GITCOMMIT := `git rev-parse HEAD`
+BUILDDATE := `date +%Y-%m-%d`
+BUILDUSER := `whoami`
+LDFLAGSSTRING :=-X github.com/zcash/lightwalletd/common.Version=$(VERSION)
+LDFLAGSSTRING +=-X github.com/zcash/lightwalletd/common.GitCommit=$(GITCOMMIT)
+LDFLAGSSTRING +=-X github.com/zcash/lightwalletd/common.Branch=$(BRANCH)
+LDFLAGSSTRING +=-X github.com/zcash/lightwalletd/common.BuildDate=$(BUILDDATE)
+LDFLAGSSTRING +=-X github.com/zcash/lightwalletd/common.BuildUser=$(BUILDUSER)
+LDFLAGS :=-ldflags "$(LDFLAGSSTRING)"
+
 # There are some files that are generated but are also in source control
 # (so that the average clone - build doesn't need the required tools)
 GENERATED_FILES := docs/rtd/index.html walletrpc/compact_formats.pb.go walletrpc/service.pb.go
@@ -120,10 +131,10 @@ dep:
 
 # Build binary
 build:
-	GO111MODULE=on go build -ldflags="-X github.com/zcash/lightwalletd/common.Version=`git describe --tags`"
+	GO111MODULE=on go build $(LDFLAGS) 
 
 build_rel:
-	GO111MODULE=on GOOS=linux go build -ldflags="-X github.com/zcash/lightwalletd/common.Version=`git describe --tags`"
+	GO111MODULE=on GOOS=linux go build $(LDFLAGS) 
 
 # Install binaries into Go path
 install:

cmd/version.go

@@ -13,6 +13,10 @@ var versionCmd = &cobra.Command{
 	Short: "Dispaly lightwalletd version",
 	Long:  `Dispaly lightwalletd version.`,
 	Run: func(cmd *cobra.Command, args []string) {
-		fmt.Println("lightwalletd version", common.Version)
+		fmt.Println("lightwalletd version: ", common.Version)
+		fmt.Println("from commit: ", common.GitCommit)
+		fmt.Println("on: ", common.BuildDate)
+		fmt.Println("by: ", common.BuildUser)
+
 	},
 }

common/common.go

@@ -18,6 +18,9 @@ import (
 
 // 'make build' will overwrite this string with the output of git-describe (tag)
 var Version = "v0.0.0.0-dev"
+var GitCommit = ""
+var BuildDate = ""
+var BuildUser = ""
 
 type Options struct {
 	BindAddr          string `json:"bind_address,omitempty"`