removes duplicated 'Shutdown' name in shutdown priority consts (#343)

packages/shutdown/order.go

plugins/analysis/client/plugin.go

plugins/analysis/server/plugin.go

plugins/analysis/webinterface/httpserver/plugin.go

plugins/autopeering/plugin.go

plugins/database/plugin.go

plugins/fpc/plugin.go

plugins/gossip/plugin.go

plugins/graph/plugin.go

plugins/messagelayer/plugin.go

plugins/metrics/plugin.go

plugins/remotelog/plugin.go

plugins/spa/drng_livefeed.go

plugins/spa/livefeed.go

plugins/spa/plugin.go

plugins/webapi/plugin.go

plugins/webapi/spammer/plugin.go