Changes suggested by linter

ua.go

@@ -22,11 +22,11 @@ type UserAgent struct {
 }
 
 var ignore = map[string]struct{}{
-	"KHTML, like Gecko": struct{}{},
-	"U":                 struct{}{},
-	"compatible":        struct{}{},
-	"Mozilla":           struct{}{},
-	"WOW64":             struct{}{},
+	"KHTML, like Gecko": {},
+	"U":                 {},
+	"compatible":        {},
+	"Mozilla":           {},
+	"WOW64":             {},
 }
 
 // Constants for browsers and operating systems for easier comparison
@@ -286,7 +286,7 @@ func Parse(userAgent string) UserAgent {
 }
 
 func parse(userAgent string) (clients properties) {
-	clients = make(map[string]string, 0)
+	clients = make(map[string]string)
 	slash := false
 	isURL := false
 	var buff, val bytes.Buffer
@@ -438,7 +438,7 @@ func (p properties) findBestMatch(withVerOnly bool) string {
 	return ""
 }
 
-var rxMacOSVer = regexp.MustCompile("[_\\d\\.]+")
+var rxMacOSVer = regexp.MustCompile(`[_\d\.]+`)
 
 func findVersion(s string) string {
 	if ver := rxMacOSVer.FindString(s); ver != "" {