Added BoxNotEmptyRule to validators

[drpayyne]

Description

Added BoxNotEmptyRule to validators where original verbose validations were removed

Fixed Issues (if relevant)

1. Fixes Plugin linemarkers is missing for interface methods #322: Implement module name validation in 'Create a plugin' and 'New module' dialog

Questions

How do we handle the issue raised at #318 (comment)?

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with integration/functional tests (if applicable)
• All automated tests passed successfully (all builds are green)

[coderimus]

Hi @drpayyne
Thank you for the investigation and implementation. A great example of the simple solution required more work during research and simple code solution. 👍