[#29] metrics: Support dump descriptions

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>

app.go

@@ -243,6 +243,17 @@ func (m *gateMetrics) SetHealth(status metrics.HealthStatus) {
 	m.provider.SetHealth(status)
 }
 
+func (m *gateMetrics) SetVersion(ver string) {
+	m.mu.RLock()
+	if !m.enabled {
+		m.mu.RUnlock()
+		return
+	}
+	m.mu.RUnlock()
+
+	m.provider.SetVersion(ver)
+}
+
 func (m *gateMetrics) Shutdown() {
 	m.mu.Lock()
 	if m.enabled {
@@ -325,6 +336,7 @@ func getKeyFromWallet(w *wallet.Wallet, addrStr string, password *string) (*ecds
 func (a *app) Wait() {
 	a.log.Info("starting application", zap.String("app_name", "frostfs-http-gw"), zap.String("version", Version))
 
+	a.metrics.SetVersion(Version)
 	a.setHealthStatus()
 
 	<-a.webDone // wait for web-server to be stopped