Ensure consistent error wrapping and error messages

[stoyanr]

How to categorize this PR?

/area quality /kind technical-debt /priority normal /platform kubevirt

What this PR does / why we need it: Ensures consistent error wrapping and error messages:

• All errors from other packages are wrapped with errors.Wrap or errors.Wrapf.
• All new errors are reported with errors.New and errors.Errorf.
• Using fmt.Errorf is avoided.
• Error messages are reworded to ensure that similar / identical errors are reported with similar / identical messages.
• String values are always quoted with %q in error messages.

Which issue(s) this PR fixes: Fixes #

Special notes for your reviewer:

Release note:

NONE

[stoyanr]

/cc @mfranczy