Move to PHP 7.1

[f3l1x]

I think it's good time to move to PHP 7.1 and drop all old versions.

From v3.2.0 it will requires PHP 7.1 and v3.1.x will support PHP >=5.6.

What do you think @haltuf @hranicka and others?

[haltuf]

Ok, for me.

[hranicka]

If v 3.x supports PHP 7.0, you should drop its support in v4.x. It's a BC-break.

I think this package is versioned accordingly to semver.org, right?

[f3l1x]

Well, @hranicka, I'm not sure it's semver.org in all details, but you're right.

2.3.x was last release for PHP 5.4.

3.1.x could be last release for PHP 5.6. But I guess we could raise it to 4.x.

[hranicka]

Yes, thanks a lot, Milan.

Nice work you are doing here :-)

[f3l1x]

I'll prepare PR in few days, I'll be glad if you join me to add strict types and other stuff. :-)

[f3l1x]

Already done.