PostgreSQL support

[Rhincodon]

What about bringing back PostgreSQL from version 2? We need to ask @Jamesking56 for pull request?

[freekmurze]

@Jamesking56 showed interest in adding PostreSQL to the db-dumper package, see this issue.
Showing interest is not a promise, so don't blame him if he takes a long time or eventually does not do it.

In any case, I'm open for PR's that adds support for other types of db's to db-dumper. If you have more questions about this, please open up an issue at the db-dumper repo.

[Jamesking56]

@Rhincodon I will add PostgreSQL support to db-dumper this weekend as I need it myself for my new SaaS project. I may even extend that later to add SQLite and MSSQL support but I'll see how I get on.

@freekmurze Is there much change needed for laravel-backup to allow it to use PostgreSQL from db-dumper?

[freekmurze]

@Jamesking56 that's great to hear! Make sure you include tests in your PR to db-dumper.

In laravel-backup, there's only {a driver type check](https://github.com/spatie/laravel-backup/search?utf8=%E2%9C%93&q=mysql) that needs to be adjusted.