README Update for xunit tips

[smudge202]

As per my comment on a previous issue, it would be good to get the Produce output on builds info added to the readme. In addition, I think the follow two tips would be great:

To automate testing of your specs:

• In project.json, add a dependency to xunit.runner.dnx (at time of writing, version 2.1.0-rc1-build204).
• Add a second command (in addition to the one used by the prebuild element) as follows:

"test": "xunit.runner.dnx"

This will make your specs appear in test explorer.

The overall output will be along the lines of:

{
    "version": "1.0.0-*",
    "commands": {
        "create-specs": "SpecFlow.Dnx",
        "test": "xunit.runner.dnx"
    },
    "scripts": {
        "prebuild": "dnx create-specs"
    },
    "frameworks": {
        "dnx46": {
            "dependencies": {
                "SpecFlow.Dnx": "1.0.0-alpha8",
                "xunit": "2.1.0",
                "xunit.runner.dnx": "2.1.0-rc1-build204"
            }
        }
    }
}

The above is obvious if you've ever done work with DNX in the past, but for people entering the arena it would be helpful I'm sure.

[stajs]

Okay, I saw your other comment first, and have updated the README for "produce outputs".

Good idea for the tips. Did you want to submit a PR (then you'll get the credit)? If so, I suggest referencing the sample project.json, in particular not including the dependencies as framework dependencies (otherwise each framework has to independently reference).

[smudge202]

Yup, I'll PR over some Readme changes.

[smudge202]

See #5