nosudo on CentOS and Fetch Changelogs on Amazon, RHEL (#448)

* Use repoquery for no sudo and avoid unintended line feed of yum or rpm. #444

* Change data type of enablerepo in config.toml. string to array

* Fetch yum changelogs at once then grep CVE-IDs

* Fix changelog parse logic and Update Gopkg

models/scanresults.go

@@ -32,7 +32,7 @@ type ScanResults []ScanResult
 // ScanResult has the result of scanned CVE information.
 type ScanResult struct {
 	ScannedAt   time.Time
-	JSONVersion string
+	JSONVersion int
 	Lang        string
 	ServerName  string // TOML Section key
 	Family      string