Updated docs for 4.7

[reginapizza]

What type of PR is this?

/kind documentation

What does this PR do / why we need it:

Updates docs for 4.7 clusters. Some previous images/instructions were out of date.

Done:

• removed some files and images for installation of pipelines/argo cd operators
• added some new images to reflect the way things currently look in 4.7
• removed mentions of 4.6
• changed any mention of Application Stages to Environments
• changed "ArgoCD" to "Argo CD" (only for docs, not for actual code)
• fixed error in filename for <Quay user>-robot-auth.json

Have you updated the necessary documentation?

• [ ] Documentation update is required by this PR.
• [x] Documentation has been updated.

Which issue(s) this PR fixes:

No issue in kam repo for this but tracked in Jira as GITOPS 545

[chetan-rns]

/retest

[chetan-rns]

@reginapizza Docs are out of date. Could you please run make cmd-docs?

[amitkrout]

@reginapizza Docs are out of date. Could you please run make cmd-docs?

+ make cmd-docs
go run tools/cmd-docs/main.go
++ git status -s
+ [[ ! -z  M docs/commands/kam_build.md ]]
+ echo 'command-documentation is out of date (run make cmd-docs).'
command-documentation is out of date (run make cmd-docs).
+ exit 1 

Test log - https://prow.ci.openshift.org/view/gs/origin-ci-test/pr-logs/pull/redhat-developer_kam/190/pull-ci-redhat-developer-kam-master-unit/1369148118699872256#1:build-log.txt%3A289

[wtam2018]

/lgtm

[wtam2018]

/approve

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: chetan-rns, wtam2018

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/redhat-developer/kam/blob/master/OWNERS)~~ [chetan-rns,wtam2018] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment