Update CLI output

[schmunk42]

While working on another PR I noticed some weird behavior of the CLI output.
A question in general: Is the isVerbose setting still needed or could most IO related output controller with the verbosity setting?

Here's my wip:
schmunk42/composer-asset-plugin@feature/skip-asset-update...schmunk42:feature/update-output

And here a screenshot how it looks with the changes above (still need some minor tuning):

A problem is, that tests would have to be adjusted here and there.
Let me know if you'd accept a PR with these updates (100% test-coverage then) - or if there are problems I might not see.

Changes are basically just adjustments to verbosity level.