Updated for Laravel 6.0

[jdanino]

Updated for Laravel 6.0

[slavarazum]

Hi, thanks for this PR.
Why minimum php version should be upped to 7.2?

[niekdemelker]

@slavarazum minimum version shouldn't be upped, laravel 5.8 needs a minimum of 7.1.3 and so does this package, so only adding laravel 6.0 should be enough.

[jdanino]

Thanks, you are right. I changed it to 7.1.3

[niekdemelker]

@slavarazum could you please merge this? That would be great.

[slavarazum]

Added comatibility in 3.2.0 version. Dropped laravel/framework dependency from compose.json, because it unnecessary with laravel/nova dependency.

Let me know if you will have any issues.