Support to manually add or load Template for ESXi Nodes

[opywan]

A template and VMspec cannot be created without vCenter however In certain circumstances, ESXi only nodes need managed by Calm (no vCenter). Templates can be manually created on ESXi but Calm DSL can't find or read them. e.g. Calm throws: "UnboundLocalError: local variable 'template_id' referenced before assignment " when querying ESXi node. This request is for support for a Template be manually added or loaded via Calm DSL tools so that Calm can manage VMs on local ESXi nodes.