PLT-6471 Properly panic when translations can't be loaded (#6414)

* PLT-6471 Properly panic when translations can't be loaded

* Print usage messages when errors occur during CLI initialization

* Reverted behaviour of FindDir and added second return value to it

* Fixed merge conflict

cmd/platform/server.go

@@ -44,12 +44,16 @@ func runServerCmd(cmd *cobra.Command, args []string) error {
 }
 
 func runServer(configFileLocation string) {
-	if errstr := utils.InitAndLoadConfig(configFileLocation); errstr != "" {
-		l4g.Exit("Unable to load mattermost configuration file: ", errstr)
+	if err := utils.InitAndLoadConfig(configFileLocation); err != nil {
+		l4g.Exit("Unable to load Mattermost configuration file: ", err)
+		return
+	}
+
+	if err := utils.InitTranslations(utils.Cfg.LocalizationSettings); err != nil {
+		l4g.Exit("Unable to load Mattermost translation files: %v", err)
 		return
 	}
 
-	utils.InitTranslations(utils.Cfg.LocalizationSettings)
 	utils.TestConnection(utils.Cfg)
 
 	pwd, _ := os.Getwd()