[Go][Server] Remove dot in golang type

[gmtstephane]

Hello, in the golang server, the model template seems to be broken when we use dot in openapi tags.
For example, for this Openapi input : https://forge.etsi.org/rep/mec/gs011-app-enablement-api/blob/master/MecAppSupportApi.yaml

The current output is :

package openapi
// DestinationInterfaceInterfaceType : Type of the interface
type DestinationInterface.InterfaceType string

// List of DestinationInterface.InterfaceType
const (
	DESTINATIONINTERFACEINTERFACETYPE_TUNNEL DestinationInterfaceInterfaceType = "TUNNEL"
	DESTINATIONINTERFACEINTERFACETYPE_MAC DestinationInterfaceInterfaceType = "MAC"
	DESTINATIONINTERFACEINTERFACETYPE_IP DestinationInterfaceInterfaceType = "IP"
)

I change from {{{name}}} to {{{classname}}}, to have the enum matching the declaration ( i.e, removing the dot)
PS : I generated to sample example but their is no case matching my problem in it.

@antihax (2017/11) @grokify (2018/07) @kemokemo (2018/09) @bkabrda (2019/07) @wing328

Thanks

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[wing328]

Shippable CI failure (not related to this PR) fixed in the master.