CNCF submission

[kalantar]

Epic to capture items related to submission of Iter8 to CNCF sandbox project.

Documentation updates

• [x] https://github.com/iter8-tools/iter8/issues/1618 (https://github.com/iter8-tools/docs/pull/108)
• [x] https://github.com/iter8-tools/iter8/issues/1619 (https://github.com/iter8-tools/docs/pull/108)
• [x] https://github.com/iter8-tools/iter8/issues/1500
• [x] release chart documentation

Code updates

• [x] https://github.com/iter8-tools/iter8/issues/1492
• [x] https://github.com/iter8-tools/iter8/issues/1606
• [x] https://github.com/iter8-tools/iter8/issues/1611
• [x] https://github.com/iter8-tools/iter8/pull/1615
• [x] release chart
• [ ] explore kubernetes gateway API
• [ ] scaling/persistence of metrics data collection

Other changes to consider

• [x] https://github.com/iter8-tools/iter8/issues/1598
• [x] https://github.com/iter8-tools/iter8/issues/1617
• [x] https://github.com/iter8-tools/iter8/issues/1620