Stabalize the PHP SDK

[welpie21]

Thank you for submitting this pull request! We appreciate you spending the time to work on these changes.

What is the motivation?

To make sure the PHP SDK is up-to-date with all the latest changes of Surreal V2 and that it is stabalized.

What does this change do?

• added Future, Range, RecordIdRange, BoundIncluded and BoundExcluded types
• added more functionality to the Duration class
• added new methods rpc, insertRelation and upsert
• added more unit tests
• Updated dependencies
• Updated readme
• changes to the unit testing setup

Fixed

• Fix CBOR encoder map for native DateTime related classes

Breaking

• renamed disconnect to close in the Surreal Class
• Moved record related classes under namespace Surreal\Cbor\Types\Record

What is your testing strategy?

I added unit tests to the PHP SDK for versions v1.4.2, v1.5.4 and 2.0.4. Currently we have code coverage of roughly 48% ( rounded down ).

Is this related to any issues?

No

Have you read the Contributing Guidelines?

• [x ] I have read the Contributing Guidelines