omdb: strip non numeric from ImdbVotes

Closes #24

util/string.go

@@ -4,17 +4,28 @@ import "regexp"
 
 var (
 	reStripNonAlphaNumeric *regexp.Regexp
+	reStripNonNumeric      *regexp.Regexp
 )
 
 func init() {
-	reg, err := regexp.Compile("[^a-zA-Z0-9]+")
+	reg1, err := regexp.Compile("[^a-zA-Z0-9]+")
 	if err != nil {
 		panic(err)
 	}
-	reStripNonAlphaNumeric = reg
+	reStripNonAlphaNumeric = reg1
+
+	reg2, err := regexp.Compile("[^0-9]+")
+	if err != nil {
+		panic(err)
+	}
+	reStripNonNumeric = reg2
 }
 
 func StripNonAlphaNumeric(value string) string {
 	// credits: https://golangcode.com/how-to-remove-all-non-alphanumerical-characters-from-a-string/
 	return reStripNonAlphaNumeric.ReplaceAllString(value, "")
 }
+
+func StripNonNumeric(value string) string {
+	return reStripNonNumeric.ReplaceAllString(value, "")
+}