Allow URL pattern generation to be skipped

[d70rr3s]

Problem/Motivation

When importing bundles some may not require a pattern to be present since may not be accessible through URL, ex: private pages that can only be accessed through some form of token or API and no pattern is required. Right now this can be done by leaving the column empty but that marks the row as incomplete. Also the code does not sanitize the input sufficiently and does not check for empty strings.

Proposed solution

Allow using some character as URL pattern skip, ex: - and check sanitize data handling.

Remaining tasks

• Add a constant for the skip value
• Refactor the code to check empty strings or skip value (produce some output in either cases)
• Write some tests