Merge pull request #21 from pieterclaerhout/master

Update detect.go to add support for tgz files

selfupdate/detect.go

@@ -72,7 +72,7 @@ func findReleaseAndAsset(rels []*github.RepositoryRelease, targetVersion string)
 	// Generate candidates
 	suffixes := make([]string, 0, 2*7*2)
 	for _, sep := range []rune{'_', '-'} {
-		for _, ext := range []string{".zip", ".tar.gz", ".gzip", ".gz", ".tar.xz", ".xz", ""} {
+		for _, ext := range []string{".zip", ".tar.gz", ".tgz", ".gzip", ".gz", ".tar.xz", ".xz", ""} {
 			suffix := fmt.Sprintf("%s%c%s%s", runtime.GOOS, sep, runtime.GOARCH, ext)
 			suffixes = append(suffixes, suffix)
 			if runtime.GOOS == "windows" {