Add support for ionic cordova namespaced commands updated on CLIv3

[neilor]

In a try to add support for newly changes on Ionic CLI v3 that adds Cordova commands to an namespace, I've added an helper that checks presence of new @ionic/cordova-cli-plugin(CHANGELOG) in dev dependencies.

That helper is used for prepend "cordova" namespace on args when starting Cordova command.

I hope that I've contribute until here.

This fixes #279

[msftclas]

@neilor,
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[msftclas]

@neilor, thanks for signing the contribution license agreement. We will now validate the agreement and then the pull request.

Thanks, Microsoft Pull Request Bot

[vladimir-kotikov]

@neilor thank you for the PR. We'll take a look at this shortly.

[terbooter]

@vladimir-kotikov,
I tested this PR on Ionic CLI v3.2 and on pure cordova project. It seems work fine.

[vladimir-kotikov]

@terbooter thanks 👍

[mlibbyrh]

I tested Ionic Cordova's launch.json using Ionic 3 and for Android. Android/IOS work great running in a browser. Each saved software change automatically builds and displays. Nice!

However, I am not able to Run Android on Device as I was able to do in Ionic 2. I was hoping this fix would address that too.

Thanks for what you did though.