[component] Xero

As a Workflow Developer
I want to be able to use the Xero connector.

Acceptance Criteria

Actions:
- [x] create Contact
- [x] create an Invoice with Invoice Line Items
- [x] create Bills with Bill Lines Items
- [x] create Quote with Quote Line Items

Triggers:
- [x] new Contact
- [x] new Invoice
- [x] new Bill

**Definition of Done:**

- [x] Unit/Integration tests
- [x] Connection setup steps
- [x] Guidejar tutorial for connection setup
- [x] Documentation is generated and available