Passing "generate" option through in compute_qname_strict

[mwatts15]

Summary of changes

Passes through an option in the compute_qname_strict interface so it raises an error in the same case as the "non-strict" version.

Checklist

• Checked that there aren't other open pull requests for
  the same change.
• Added tests for any changes that have a runtime impact.
• Checked that all tests and type checking passes.
• For changes that have a potential impact on users of this project:
  • Updated relevant documentation to avoid inaccuracies.
  • Considered adding additional documentation.
  • Considered adding an example in ./examples for new features.
  • Considered updating our changelog (CHANGELOG.md).
• Considered granting push permissions to the PR branch,
  so maintainers can fix minor issues and keep your PR up to date.

[coveralls]

Coverage remained the same at 88.267% when pulling 42950ab on mwatts15:master into d5eb957 on RDFLib:master.

[aucampia]

Looks good to me, thanks for the fix.

[ghost]

nice one