In restore errors, mention which package had the problem.

This improves the situation when the user runs `godep restore`
and sees a few instances of "restore, during download dep" errors.
Previously, it was not mentioned which packages failed to download.
Turning on -v verbose mode was not a good solution since it prints
too much other information for successfully processed packages.

Changelog.md

@@ -1,3 +1,7 @@
+# v31 2015/12/2
+
+* In restore, mention which package had the problem -- @shurcool
+
 # v30 2015/11/25
 
 * Add `-t` flag to the `godep get` command.

restore.go

@@ -29,15 +29,15 @@ func runRestore(cmd *Command, args []string) {
 	for _, dep := range g.Deps {
 		err := download(dep)
 		if err != nil {
-			log.Println("restore, during download dep:", err)
+			log.Printf("restore, during download dep %q: %v\n", dep.ImportPath, err)
 			hadError = true
 		}
 	}
 	if !hadError {
 		for _, dep := range g.Deps {
 			err := restore(dep)
 			if err != nil {
-				log.Println("restore, during restore dep:", err)
+				log.Printf("restore, during restore dep %q: %v\n", dep.ImportPath, err)
 				hadError = true
 			}
 		}

version.go

@@ -5,7 +5,7 @@ import (
 	"runtime"
 )
 
-const version = 30
+const version = 31
 
 var cmdVersion = &Command{
 	Usage: "version",