Sentry integration (#591)

Use sentry echo integration to send errors

Only capture errors not already handled by echo

Add sentry panic handler

Add sentry library

Add sentry init

Add sentry config

Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/api/pulls/591

pkg/config/config.go

@@ -49,6 +49,7 @@ const (
 	ServiceTimeZone              Key = `service.timezone`
 	ServiceEnableTaskComments    Key = `service.enabletaskcomments`
 	ServiceEnableTotp            Key = `service.enabletotp`
+	ServiceSentryDsn             Key = `service.sentrydsn`
 
 	DatabaseType                  Key = `database.type`
 	DatabaseHost                  Key = `database.host`