func Create() error {
	return CreateFile(DefaultPkgName + "/" + DefaultPkgName + ".go")
}
Create will create a file named version.go in the directory you ran
'go generate', that will contain three constants:

VgVersion: The version of your repo as given by 'git describe --tags'
plus the DirtyString variable if you have uncommitted changes.

VgHash: The SHA1 hash of your current commit.

VgClean: indicates whether your build is clean or it includes uncommitted changes.
package vergen
import (
	"errors"
	"fmt"
	"log"
	"os"
	"os/exec"
	"strings"
	"time"
)
const (
	DefaultPkgName     = "version"
	DefaultDirtyString = "+"
	DefaultTimeout     = 15 * time.Second
)
var DirtyString = DefaultDirtyString
var IgnoreFiles = []string{"version.go"}
var Timeout = DefaultTimeout
type versionData struct {
	describeTags string
	commit       string
	dirty        bool
}