Mock out the underlying segment-io call.

TE-532
Fix another analytics.init secret error message (noise).
Pipe analytics client output to stdout instead of devnull.
Combine payment and intro step
Merge pull request #6240 from edx/benp/fix-analytics-init

Mock out the underlying segment-io call.
Use current full name as placeholder text
Merge pull request #6263 from edx/renzo/full-name-placeholder

Use current full name as placeholder text
Merge pull request #6260 from edx/will/combine-intro-and-make-payment

Combine payment and intro step
Add the activate account step to the verified workflow.

Changing approach such that email activation is not a step.

Removing stale line of code.