CNCF submission

[kalantar]

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

Documentation updates

• Remove term *experiment* from documentation #1618 (remove iter8 cli docs#108)
• remove iter8 command #1619 (remove iter8 cli docs#108)
• Describe relationship to other similar tools #1500
• release chart documentation

Code updates

• Remove public facing iter8 commands #1492
• Clean up makefile after dockerfile changes  #1606
• Remove duplicate payload templates for http and slack #1611
• Delete extraneous files #1615
• release chart
• explore kubernetes gateway API
• scaling/persistence of metrics data collection

Other changes to consider

• Bump go version for workflows #1598
• Align iter8 to match terminology used in docs #1617
• Proposal: modify metrics endpoints to make more similar #1620