V2 refactor

[gwleuverink]

This PR moves all of the code that does not directly involve Electron from the Electron to the Support namespace.

• Several traits and methods previously spread across commands are now encapsulated within the Native\Support\Bundler class.
• Additionally I added a native:install script to post-update-cmd automatically.

There is room for improvement, but incrementally I think this is a good first step.

Appreciate any thoughts on this!

[gwleuverink]

I discussed this with @SRWieZ. We concluded that it is better to put everything under the Desktop namespace.

I updated the PR to use this structure:

/
└── src
    ├── NativeServiceProvider.php
    ├── ... etc
    ├── Builder
    │   ├── Builder.php
    │   └── ...
    └── Drivers
        └── Electron
            ├── ElectronServiceProvider.php
            └── ...

The old Electron package now lives in Native\Desktop\Drivers\Electron

The Builder related traits I mentioned moved to the Native\Desktop\Builder class.