Add published vendor translation

[roseffendi]

This PR include published vendor translation at generation. I think it will come handy to generate the published package translation all at once.

[martinlindhe]

If this is useful, then sure we can merge it. But I want it behind a command line switch, and disabled by default. The reason is that scanning the vendor folder might add quite some time when running this package (if the vendor folder is big).

You can see how command line switches is currently handled in https://github.com/martinlindhe/laravel-vue-i18n-generator/blob/master/src/Commands/GenerateInclude.php

[roseffendi]

Yes, i can make command line switch for that. How would you like it to be formatted ?

Currently it's like this.

[en] => [
    "yes" => "Yes",
    "no" => "No"
    "vendor" => [
        "package-hint-one" => [
            "package-one-lang" => "Translation"
        ],
        "package-hint-two" => [
            "package-two-lang" => "Translation"
        ],
    ]
]

[martinlindhe]

The formatting looks good, thank you for your work on this!

[martinlindhe]

All good, thanks alot for this!