Add project structure of terraform provider and cockroach cluster functionality

[prafull01]

• Added the basic project structure.
• Added functionality to create/update/delete the cockroach cluster using TF provider

[marksoper]

@prafull01 What is the difference between the cluster "resource" and the cluster "data source"?

[prafull01]

resource is termed as the resource which we are trying to create. For example we are creating the cockroach-cluster we will define it as:

resource "cockroach_cluster" "cockroach" {
    name           = "cockroach-cluster"
    cloud_provider = "CLOUD_PROVIDER_GCP"
    spec = {
    serverless = {
        regions = ["us-east1"]
        spend_limit = 0
        }
    }
}

data source is used to the load the existing resource into the terraform state. Lets say we want to load the existing cluster in the terraform state to create the SQL User in the cluster, we will add the following in terraform file:

data "cockroach_cluster" "existing" {
    id = "clusterid"
} 

This will read the cluster and load into the existing object so that we can use further information we fetched in creating the SQL User

[marksoper]

@prafull01 what are you thinking about in terms of overall testing strategy?

[prafull01]

Testing strategy is yet to be determined, I have added this only as scaffolding