Fix #285: Allow setting of task name in manifest with override from commandline flag

[geauxvirtual]

Fixes #285

Summary of changes:

• Only uses --name flag for setting name if --name was set on the command line. Add name field to task manifest will set the name for a task.
• Add a name field to a task manifest will set the name of the task.
• Updated example mock-file.json and mock-file.yaml to include name field

Testing done:

• Verified task name can be set from task manifest or overriding from --name flag

Updated mock-file.json

{
    "version": 1,
    "name": "mock-file",
    "schedule": {
        "type": "simple",
        "interval": "1s"
    },
    "max-failures": 10,
    "workflow": {
        "collect": {
            "metrics": {
                "/intel/mock/foo": {},
                "/intel/mock/bar": {},
                "/intel/mock/*/baz": {}
            },
            "config": {
                "/intel/mock": {
                    "name": "root",
                    "password": "secret"
                }
            },
            "process": [
                {
                    "plugin_name": "passthru",
                    "process": null,
                    "publish": [
                        {
                            "plugin_name": "mock-file",
                            "config": {
                                "file": "/tmp/snap_published_mock_file.log"
                            }
                        }
                    ]
                }
            ]
        }
    }
}

@intelsdi-x/snap-maintainers

[lmroz]

https://github.com/intelsdi-x/snap/blob/master/core/task_test.go#L139
Apart from that, LGTM 👍

[jcooklin]

👍 🚢 it

[geauxvirtual]

Closing this as #1127 covers this issue.