Add pipeline configuration details in pipeline client

[erudinsky]

While using pipeline client, I noticed that configuration returns just Type and the rest is dropped (?). API, based on pipeline type (i.e. yaml or designerJson), returns additional fields:

yaml:

    "configuration": {
        "path": "azure-pipelines.yml",
        "repository": {
            "id": "eb96368e-87df-4744-9448-023a1ae6eb53",
            "type": "azureReposGit"
        },
        "type": "yaml"
    },