Vendor godep v79 and use it

vendor/github.com/tools/godep/util.go

@@ -0,0 +1,60 @@
+package main
+
+import (
+	"fmt"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+)
+
+// Runs a command in dir.
+// The name and args are as in exec.Command.
+// Stdout, stderr, and the environment are inherited
+// from the current process.
+func runIn(dir, name string, args ...string) error {
+	_, err := runInWithOutput(dir, name, args...)
+	return err
+}
+
+func runInWithOutput(dir, name string, args ...string) (string, error) {
+	c := exec.Command(name, args...)
+	c.Dir = dir
+	o, err := c.CombinedOutput()
+
+	if debug {
+		fmt.Printf("execute: %+v\n", c)
+		fmt.Printf(" output: %s\n", string(o))
+	}
+
+	return string(o), err
+}
+
+// driveLetterToUpper converts Windows path's drive letters to uppercase. This
+// is needed when comparing 2 paths with different drive letter case.
+func driveLetterToUpper(path string) string {
+	if runtime.GOOS != "windows" || path == "" {
+		return path
+	}
+
+	p := path
+
+	// If path's drive letter is lowercase, change it to uppercase.
+	if len(p) >= 2 && p[1] == ':' && 'a' <= p[0] && p[0] <= 'z' {
+		p = string(p[0]+'A'-'a') + p[1:]
+	}
+
+	return p
+}
+
+// clean the path and ensure that a drive letter is upper case (if it exists).
+func cleanPath(path string) string {
+	return driveLetterToUpper(filepath.Clean(path))
+}
+
+// deal with case insensitive filesystems and other weirdness
+func pathEqual(a, b string) bool {
+	a = cleanPath(a)
+	b = cleanPath(b)
+	return strings.EqualFold(a, b)
+}